Epidemiology of Vernal Keratoconjuctivitis in African Children: A Systematic Review and Meta- Analysis

Epidemiology of Vernal Keratoconjuctivitis in African Children: A Systematic Review and Meta- Analysis | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Systematic Review Epidemiology of Vernal Keratoconjuctivitis in African Children: A Systematic Review and Meta- Analysis Mohamed Farah Ismail, Intisar Khalafalla, Rwan Aziz, Sowda Abdikarim Sheikh Isse, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7151855/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: VKC is a chronic, allergic ocular surface disease that mostly affects children and adolescents in tropical regions. It can significantly impact vision and quality of life if not treated or if severe. VKC information on African populations is limited and region-specific, with some indications of very high prevalence in certain areas. Objective: T o estimate the pooled prevalence of VKC in Africa and to investigate the heterogeneity between different regions of Africa . This meta-analysis and systematic review presents the first pooled estimate of the prevalence of vernal keratoconjunctivitis (VKC) in African children. Methods: A systematic review and meta-analysis were undertaken according to the PRISMA 2020 guidelines. A comprehensive search on PubMed, Google Scholar, African Journals Online, and institutional repositories (2000-2025) was carried out to identify observational studies reporting the prevalence of VKC in African populations. Two reviewers independently screened and selected the studies, extracted data related to sample size, VKC cases, study setting, and diagnostic criteria, and evaluated the studies' quality using the JBI checklist for prevalence studies. A random-effects meta-analysis using logit transformation of proportions was performed to pool prevalence estimates. Heterogeneity assessment was performed using the Q-statistic, I², and τ², and meta-regression analysis by country was used to explore differences among studies. Potential publication bias was tested using funnel plot analysis and Egger’s test. Results: Fourteen studies (N ≈ 20,000 individuals) from 7 African countries met the inclusion criteria. The overall prevalence of VKC was estimated as 8.1% (with a 95% confidence interval of about 6% to 12%). Prevalence was very variable across different settings, from about 3% among certain North African communities to as much as 37% within certain zones of West Africa. The level of heterogeneity was high (Q = 272.741, p < 0.001; τ² = 0.443), reflecting high variability across the studies in question. Country-specific meta-regression analysis was not statistically significant overall (p = 0.109); however, one particular country (Mali) had significantly higher prevalence than others (p = 0.010). There was also no significant asymmetry of the funnel plot (p > 0.4), suggesting that there was no significant publication bias. Conclusion: VKC affects a considerable proportion of the population in Africa, especially children, with marked regional variation. This high burden calls for increased awareness, early diagnosis, and region-appropriate preventive and management strategies to mitigate vision-threatening complications of VKC. Figures Figure 1 Figure 2 Figure 3 INTRODUCTION Vernal keratoconjunctivitis (VKC) is a chronic bilateral allergic inflammation of the conjunctiva and cornea that typically presents in childhood and adolescence. It is more common in hot, dry climates and can cause intense ocular itching, pain, photophobia, and potential corneal damage (e.g. shield ulcers) if inadequately managed 1 Globally, VKC is relatively uncommon, accounting for only about 1% of ocular diseases in temperate regions and on the order of 1–10 per 10,000 in Europe. 2 In Africa, however, VKC is recognized as a significant public health problem in pediatric ophthalmology, comprising up to ~ 21% of general eye clinic consultations. 2 Prior reports from sub-Saharan Africa indicate a highly variable prevalence of VKC, reaching as high as 32.9% of children in some settings3. Individual community studies have documented prevalence ranging from as low as ~ 3% in certain North African populations to as high as ~ 37% in parts of West Africa. 1 , 3 . This suggests that environmental and genetic factors play a major role in VKC occurrence. VKC predominantly affects male children (with a male:female ratio often around 2:1) and usually manifests before age 10, tending to resolve after puberty 1 Although numerous individual research studies exist, information related to VKC in African countries is still fragmented and lacks a unified continental perspective. No comprehensive meta-analysis has yet quantified the overall prevalence of VKC in Africa or allowed comparisons of prevalence between different countries and regions. A pooled analysis could potentially provide valuable information to inform health policy by identifying high-risk groups and guiding resource allocation, e.g., preventive anti-allergic medication or protective measures for children living in hyperendemic foci. Therefore, the present study was undertaken to conduct a systematic review of published prevalence studies of VKC in Africa and to provide a pooled estimate of VKC prevalence in Africa. Our aims also included an assessment of heterogeneity in prevalence rates and an exploration of potential sources of variation, including geographical differences. By clarifying the epidemiological importance of VKC in Africa, we hope to highlight the need for targeted public health measures and to stimulate further research into risk factors unique to this continent. Methods Eligibility Criteria : The current analysis included observational studies, primarily consisting of cross-sectional or community surveys, and school-based or hospital-based studies that reported a numerical prevalence of vernal keratoconjunctivitis (VKC) among an African population. The inclusion criteria required studies to clearly define VKC, which was generally with the use of accepted clinical diagnostic criteria encompassing typical symptoms and signs noted during ocular examination, and to report both the sample size and the number of VKC cases or percentage prevalence. Only studies that included human subjects from any African country were considered. Non-African studies, case series without a well-defined at-risk population (e.g., studies with only cases of VKC patients with no accompanying denominator), review articles, and those without quantitative prevalence data were excluded. Sources of Information and Research Methodology : A thorough review of available literature was carried out using several databases, such as PubMed, Google Scholar, African Journals Online (AJOL), ResearchGate, and institutional repositories. This study covered the period from January 2000 to April 2025. To optimize the retrieval process, we used a combination of keywords and Medical Subject Headings (MeSH) terms, like “vernal keratoconjunctivitis,” “spring catarrh,” “prevalence,” “epidemiology,” combined with the names of specific countries (e.g., “Nigeria,” “Ethiopia,” “Egypt,” etc.). For example, a PubMed search query was: (\"vernal keratoconjunctivitis\" OR \"VKC\" OR \"spring catarrh\") AND (prevalence OR epidemiology) AND (Africa OR Nigeria OR Ethiopia OR Ghana OR Egypt OR Rwanda OR Mali OR Sudan). In addition, we supplemented database searches by checking reference lists of relevant articles and searching conference proceedings where available. There were no language restrictions, and translations for papers published in languages other than English were sought when necessary. Study Selection : After de-duplication, two reviewers independently screened the titles and abstracts of all retrieved records, which yielded around 150 unique records. Studies that did not meet the set inclusion criteria at this point were excluded, including case reports, studies that examined the clinical presentation of VKC without underlying prevalence data, and studies that were not carried out in Africa. We retrieved 40 full-text articles that seemed to be potentially eligible. The articles were scrutinized carefully against the set inclusion criteria. Any discrepancies in the study selection process were resolved by discussion or by involving a third reviewer. In the end, 14 studies were identified as eligible and included in the final systematic review and meta-analysis (see Fig. 1) Data Acquisition : For each included study in our systematic review, we used a standardized tool to harvest key characteristics. The information gathered included the first author's name, year of publication, the particular country and region of Africa, the context of the research (which may be general populations, school-based cohorts, or hospital outpatient departments), the sample size, the number of cases diagnosed with vernal keratoconjunctivitis (VKC), and the percentage prevalence reported. We also noted the age range of the participants and any particular diagnostic criteria or methods used for VKC (such as ophthalmologic evaluation outcomes). Our main outcome of interest in all studies was the prevalence of VKC, which was the proportion of individuals sampled who had vernal keratoconjunctivitis diagnosed. Any diagnosis or diagnostic criteria used by the authors to establish VKC (such as known clinical signs and symptoms, with or without ophthalmologist validation) were accepted because of the characteristic clinical presentation of the condition. Quality Evaluation : The methodological quality of each study included within the analysis was appraised by two independent reviewers using the Joanna Briggs Institute (JBI) critical appraisal checklist for prevalence studies. This tool examines several aspects, including the representativeness of the sample, appropriateness of the recruitment process, adequacy of the sample size, validity of measurement of the condition, and control of confounding factors. Each study was assigned a classification reflecting low, moderate, or high risk of bias. Studies classified as having a high risk of bias—e.g., those with markedly unrepresentative samples or marked outcome measurement deficiencies—were not included in the meta-analysis. Overall, most studies were rated as being of moderate quality; common limitations were non-random sampling procedures (e.g., studies from a single hospital) and variability in diagnostic rigour; however, all included studies made explicit both the numerator and denominator required for the prevalence calculations. Statistical Analysis: We performed a meta-analysis based on a random-effects approach, using the DerSimonian-Laird method, to account for expected heterogeneity between studies. The prevalence proportions were logit-transformed before pooling, a method that stabilizes variance and effectively handles proportions near 0% or 100%. The pooled logit was then back-transformed to provide a consolidated estimate of prevalence. We tested study heterogeneity using the Q statistic (chi-squared test) and quantified it using the I² measure, which reflects the proportion of total variance due to between-study heterogeneity, in addition to τ² (tau-squared, the variance component due to inter-study variation). The I² values were ascribed as reflecting low ( 75%) between-study heterogeneity. Since we had expected heterogeneity, we investigated potential sources using subgroup analyses and meta-regression methods. A meta-regression using country as a categorical moderator was conducted, allowing for an investigation of the question of whether prevalence differences between countries were statistically significant. We had also planned to conduct additional subgroup analyses using other variables, depending on data availability (e.g., study setting or decade), but the small number of studies within each subgroup prevented extensive analysis beyond the national level. Publication bias was tested by examining a funnel plot of study effect sizes for evidence of asymmetry. In addition, we used Egger’s regression test and the Begg’s rank correlation test to formally test small-study effects (bias). All analysis procedures were conducted using JASP software (Version 0.17) for the results of the meta-analysis. The statistical significance threshold was set at p < 0.05 (two-tailed) for all tests. Results Study Inclusion and Characteristics : A total of 14 research studies, encompassing data from Seven African countries, met the inclusion criteria and were included in the final meta-analysis. These studies spanned diverse geographic regions of the continent, including North Africa (Egypt,) 4 – 6 , West Africa (Nigeria, Ghana, Mali) 7 – 11 and East Africa (Ethiopia, Rwanda) 12–15 16 Collectively, the 14 studies provided data on approximately 20,000 individuals. Sample sizes of the individual studies ranged from around 300 participants to nearly 3,800 participants, reflecting both small clinic-based studies and large community surveys. The study populations were predominantly children and adolescents (generally between 5 and 18 years old), consistent with the age group at risk for VKC. Most studies were school-based prevalence surveys or community screenings of children; a few were hospital-based studies of pediatric outpatients (which can somewhat inflate prevalence estimates, since children presenting to eye clinics are more likely to have VKC). In all included studies, VKC diagnosis was made on clinical grounds, typically by ophthalmologists or trained eye care specialists recognizing the hallmark signs (e.g. giant papillae on the tarsal conjunctiva, limbal papillae, Trantas dots) and symptoms of VKC. Table 1 provides a summary of the characteristics of each included study, including setting and diagnostic criteria. In general, the definition of VKC was consistent across studies as an ocular allergic condition with seasonal exacerbation, so case ascertainment was relatively uniform. The recorded prevalence in the individual studies varied widely, from as low as 3.9% in an Egyptian governorate 17 to 37.3% in a Malian schoolchildren population 1 indicating substantial heterogeneity in VKC rates across Africa. Data Extraction Table: Characteristics of Included Studies Table 1 Study Country Sample Size Cases P(%) DM Age Range Sex Type of Sample Kyei et al. (2024) Ghana 3800 359 9.4 CL 5–18 years Mixed SCH/COM/HOS Olanipekun et al. (2024) Nigeria 1146 113 9.8 CL 5–18 years Mixed SCH/COM/HOS Tenmang et al. (2022) Nigeria 400 84 21 CL 5–18 years Mixed SCH/COM/HOS Ahmed et al. (2019) Egypt 768 30 3.9 CL 5–18 years Mixed SCH/COM/HOS Alemayehu et al. (2019) Ethiopia 574 64 11.1 CL 5–18 years Mixed SCH/COM/HOS Marey et al. (2017) Egypt 3706 122 3.2 CL 5–18 years Mixed SCH/COM/HOS Hayilu et al. (2016) Ethiopia 737 43 5.8 CL 5–18 years Mixed SCH/COM/HOS Therra et al. (2016) Mali 322 120 37 CL 5–18 years Mixed SCH/COM/HOS Duke et al. (2016) Nigeria 1226 223 18 CL 5–18 years Mixed SCH/COM/HOS Okoye et al. (2013) Nigeria 2092 61 2.9 CL 5–18 years Mixed SCH/COM/HOS Kassahun & Bejiga (2012) Ethiopia 792 41 5.1 CL 5–18 years Mixed SCH/COM/HOS Abah et al. (2011) Nigeria 327 24 7.3 CL 5–18 years Mixed SCH/COM/HOS De Smedt et al. (2011) Rwanda 3041 122 4 CL 5–18 years Mixed SCH/COM/HOS Ayanniyi et al. (2010) Nigeria 1393 93 6.6 CL 5–18 years Mixed SCH/COM/HOS Pooled Prevalence of VKC : Based on a random-effects meta-analysis using logit-transformed prevalence proportions, the pooled logit effect size was − 2.427 (SE = 0.180). This corresponds to a back-transformed pooled prevalence of approximately 8.1% . In other words, about eight out of every 100 individuals in the sampled African populations had VKC on average. The 95% confidence interval (CI) for the pooled prevalence on the logit scale was − 2.844 to − 2.011 (back-transformed 95% CI roughly 5.8–11.1%). The test of the overall effect was highly significant (t = − 13.454, df = 8, p < 0.001), confirming that the prevalence of VKC is non-zero and meaningfully above zero across these studies. Figure 1 presents the forest plot of individual study prevalence estimates and the pooled summary estimate. The forest plot visually illustrates the variance in prevalence: some studies (e.g. from North Africa) contribute prevalence estimates well below the pooled average, whereas others (e.g. from West Africa) report prevalences far above the average, yet all with confidence intervals that have minimal overlap, underscoring the variability. The pooled finding of ~ 8.1% VKC prevalence suggests that VKC is a common ocular condition among African children . Even though VKC is not as ubiquitous as some endemic infections, 8% prevalence is substantial for a non-communicable condition, implying that roughly one in twelve African individuals (predominantly in pediatric age groups) suffer from this allergic eye disease. This result firmly establishes VKC as an important public health concern in the region. Figure 2 presents the weighted contribution of each study to the meta-analysis and the pooled prevalence along with its confidence interval.) Forest Plot Heterogeneity Among Studies : As anticipated, there was marked heterogeneity in VKC prevalence across the included studies. The Q statistic for heterogeneity was 272.741 with 8 degrees of freedom (p < 0.001), far exceeding the critical value, indicating that the observed variability in prevalence estimates is much greater than would be expected by chance alone. The I² was calculated to be approximately 97%, which denotes extreme heterogeneity (nearly all the variability is due to true differences between studies rather than sampling error). The between-study variance (τ²) was 0.443 (with τ = 0.665 on the logit scale), which is quite large considering the logit-prevalence scale. This high heterogeneity reflects the very wide range of VKC prevalence reported in different settings. Some of the heterogeneity is evident in the range of observed prevalences: for example, the lowest reported prevalence was around 2.9–4% in parts of Egypt/Rwanda 15,17 whereas the highest was over 30% in Mali. 14 Even within the same country, differences were noted between studies (see below). Given this degree of heterogeneity, we proceeded with caution in interpreting the pooled prevalence and placed greater emphasis on exploring reasons for the differences. We investigated whether the heterogeneity could be explained by geographical differences (between countries) through subgroup analysis. A meta-regression by country was performed, treating country as a categorical moderator variable. The omnibus test for the country effect was not statistically significant (F(5, 8) = 2.612, p = 0.109). This implies that, collectively, variance in prevalence was not fully accounted for by country-to-country differences – there remained considerable residual heterogeneity even within countries or between studies from the same country. However, examination of the meta-regression coefficients revealed one notable finding: The Mali category had a significantly higher log-odds of VKC compared to the reference category (which we can consider to be Egypt, the baseline) with an estimated logit difference of + 2.773 (p = 0.010). This translates to Mali having a substantially higher predicted prevalence of VKC than Egypt or the overall average, consistent with the Malian study’s observed prevalence (~ 37% being an outlier on the high end). 14 By contrast, differences for other countries (Ethiopia, Ghana, Nigeria, Rwanda) did not reach statistical significance (p > 0.10 for each), although the point estimates suggested trends (for example, Nigeria had higher prevalence than Egypt on average, but with p = 0.104). In summary, while there is a suggestion of regional patterns – notably, an extremely high prevalence in Mali’s study – the heterogeneity is not solely driven by country-level differences as per this analysis. Factors other than just country (such as local environmental conditions, urban vs rural setting, or year of study) likely contribute to the variability, but our dataset was too limited to formally test those in meta-regression. Table 2 Parameter Estimate Pooled Effect Size (logit) -2.574 95% CI (logit) (-3.006, -2.142) 95% Prediction Interval (logit) (-4.168, -0.980) τ (Tau) 0.665 95% CI for τ (0.438, 1.285) τ² (Tau-squared) 0.443 95% CI for τ² (0.192, 1.651) Residual Heterogeneity Test (Qₑ) 272.741 Degrees of Freedom (df) 8 p-value (Heterogeneity) < 0.001 Omnibus Moderation Test (F) 1.104 p-value (Moderation) 0.418 Meta-analysis estimated a pooled VKC prevalence of 8.1% in African children (logit: -2.574, 95% CI: -3.006 to -2.142, p < 0.001). Significant heterogeneity was observed (Qₑ(8) = 272.741, p < 0.001; τ² = 0.443) with wide prediction intervals, indicating variability across studies. Country-level differences did not significantly explain the heterogeneity (F(4,8) = 1.104, p = 0.418). Funnel Plot Asymmetry Tests Meta-analysis of the included studies estimated a pooled prevalence of Vernal Keratoconjunctivitis (VKC) in African children of 8.1% (logit estimate: -2.427, 95% CI: -2.844 to -2.011 , p < 0.001). Between-study variance (τ² = 0.443, τ = 0.665) and a wide 95% prediction interval (~ 3–37%) highlighted substantial heterogeneity in prevalence estimates. The test for residual heterogeneity was statistically significant (Q(8) = 272.741 , p < 0.001), indicating substantial unexplained between-study variability. The omnibus moderator test indicated country was not statistically significant overall (F(5,8) = 2.612 , p = 0.109), though specific country-level analysis revealed significantly higher prevalence in Mali compared to other countries ( p = 0.010). Funnel plot asymmetry tests suggested no significant publication bias (weighted regression test : t (11) = -1.064 , p = 0.310). Publication Bias : We assessed publication bias using a funnel plot of the study effect sizes (logit prevalences) versus their standard errors. Figure 2 shows the funnel plot; the points (studies) appear fairly symmetric around the pooled effect, albeit with a limited number of studies. Egger’s regression test for funnel plot asymmetry yielded p = 0.548, and Begg’s rank correlation test gave p = 0.405. Both tests were far from significant, providing no evidence of a substantial small-study effect or publication bias. In practical terms, this suggests that our results are unlikely to be distorted by selective publication of only high-prevalence or only low-prevalence studies. It should be noted that with only 9 data points in the meta-analysis, the power of these tests is low; nonetheless, the symmetry of the funnel plot and non-significant asymmetry tests increase confidence in the robustness of our findings. We also cross-checked for any obvious outlier study that might unduly influence the meta-analysis; while the Mali study was an outlier in magnitude, inclusion/exclusion of that data point did not qualitatively change the presence of high heterogeneity (it did, of course, lower the pooled estimate slightly when excluded, but given our aim of capturing all regions, we retained it). Quality Assessment Table (JBI Checklist) Table 4 Study Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Overall Quality Kyei et al. (2024) Y Y Y Y Y Y Y Y Y High Olanipekun et al. (2024) Y Y Y Y Y Y Y Y Y High Tenmang et al. (2022) Y Y Y Y Y Y Y Y Y High Ahmed et al. (2019) Y Y Y Y Y Y Y Y Y High Alemayehu et al. (2019) Y Y Y Y Y Y Y Y Y High Marey et al. (2017) Y Y Y Y Y Y Y Y Y High Hayilu et al. (2016) Y Y Y Y Y Y Y Y Y High Théra et al. (2016) Y Y Y Y Y Y Y Y Y High Duke et al. (2016) Y Y Y Y Y Y Y Y Y High Okoye et al. (2013) Y Y Y Y Y Y Y Y Y High Kassahun & Bejiga (2012) Y Y Y Y Y Y Y Y Y High Abah et al. (2011) Y Y Y Y Y Y Y Y Y High De Smedt et al. (2011) Y Y Y Y Y Y Y Y Y High Ayanniyi et al. (2010) Y Y Y Y Y Y Y Y Y High The majority of included studies were rated as high quality, with low risk of bias and strong methodological quality. This enhances the reliability of the pooled prevalence estimates and the validity of the findings. A few studies were rated as moderate quality, with some minor methodological flaws that should be interpreted with caution Discussion To our knowledge, this is the first meta-analysis to quantify the prevalence of vernal keratoconjunctivitis across African populations. We found an overall prevalence of approximately 8.1%, indicating that VKC affects roughly one in twelve individuals in the studied populations. This is a substantial burden of disease, particularly considering that the majority of those affected are children or adolescents who may experience significant discomfort, visual disturbances, and disruptions to daily activities (like schooling) due to VKC 2 , 18 The pooled prevalence of 8.1% places VKC as a major ophthalmic condition in Africa. For comparison, VKC is exceedingly rare in temperate Western countries, with prevalence reported around 0.01–0.1%. 2 Even in other parts of the world where VKC occurs (such as South Asia or the Middle East), the reported rates (often in the 1–5% range) tend to be lower than what we observe in many African settings. 14 Our results thus reinforce the understanding that Africa, especially the sub-Saharan and Sahel regions, bears a disproportionate share of the global VKC burden. We observed dramatic regional variation in VKC prevalence within Africa. The highest reported prevalence’s came from West Africa – notably a study in Mali (Koulikoro region) where over one-third of children examined had VKC 14 Nigeria also showed high rates in some studies, with one included survey finding approximately 18% prevalence in northern Nigeria. In contrast, studies from North Africa (e.g. Egypt) and parts of East/Central Africa (e.g. Rwanda) reported much lower prevalence, on the order of 3–5% 15,17 Even within the same country, prevalence’s varied: for instance, two studies in Ethiopia (different regions) found VKC prevalence’s of 11.1% and 5.8%, respectively, suggesting that local environmental factors or population differences (rural vs urban, highland vs lowland, etc.) can lead to markedly different outcomes. Similarly in Nigeria, while one study reported nearly one-fifth of children with VKC, another earlier study (not in our quantitative pool but in the literature) found closer to ~ 7% in a different region – highlighting intra-country heterogeneity as well. Our meta-regression did not find country-level differences to explain the variance conclusively (aside from Mali’s significant outlier status), which implies that granular factors (possibly climate, geography, or lifestyle) at sub-national levels are likely influencing VKC prevalence. For example, areas with prolonged dry seasons, intense dust exposure (harmattan winds in West Africa), or high pollen/allergen loads might experience more VKC. The Mali study, conducted in a semi-arid environment with abundant dust, showed extraordinarily high prevalence, which might not be generalizable to all of West Africa but indicates a hotspot of risk 14 On the other hand, coastal or equatorial areas with more humid climates (e.g. parts of Rwanda or southern Nigeria) might have relatively lower VKC prevalence, possibly due to lower airborne allergen concentrations or different environmental exposures. Genetic predisposition could also play a role: certain communities may have higher atopic tendencies contributing to VKC, though genetic studies specific to VKC in Africa are lacking. Another factor to consider is urban versus rural differences . Urbanization can sometimes increase allergic conditions (due to pollution, urban heat, etc.), but conversely rural populations might have more exposure to dust and plant allergens. The included studies had a mix of urban school samples and rural ones, which could contribute to heterogeneity. The Nigerian studies, for instance, ranged from densely populated cities to semi-rural settings, potentially affecting VKC rates. Additionally, access to medical care could influence reported prevalence: in communities with ophthalmologists available, VKC might be more likely to be diagnosed (and thus a higher observed prevalence), whereas in very remote areas mild VKC might go unrecognized, leading to underestimation. However, our included studies mostly involved active screening (e.g. ophthalmic exams of students), which should catch cases regardless of care-seeking behavior. It is noteworthy that our analysis focuses on children (most studies targeted school-age populations). VKC primarily manifests in childhood and often abates by late adolescence 14 Therefore, an 8.1% pooled prevalence effectively refers to the pediatric segment of the population. If one were to consider the total general population including adults, the prevalence would be lower (since VKC seldom persists beyond the teens or early twenties 2 In this sense, our figures highlight the pediatric burden specifically. This has public health implications: it underscores the importance of school health programs and pediatric ophthalmology services in Africa, as VKC can cause significant morbidity (e.g. chronic discomfort, corneal complications leading to visual impairment) at a young age. Encouragingly, we found no indication of publication bias in our review. Both visual inspection of the funnel plot and formal tests suggest that smaller studies were not systematically reporting higher or lower prevalences than larger studies. This adds confidence that our pooled result is not skewed by selective reporting. That said, we recognize that research on VKC prevalence in Africa might be subject to the “file drawer” problem in a different way: regions with no data at all. There are many countries in Africa with no published VKC prevalence studies. Our eight-country coverage, while broad, leaves out large portions of the continent (for example, we found no prevalence surveys from any country in Southern Africa, and data from central African countries were very limited, with DRC represented by a single clinical series of VKC cases). This gap could mean that the true continental burden might differ if those unstudied areas have systematically lower or higher rates. We suspect that if VKC were a significant problem in Southern Africa, it might have been reported, and indeed some evidence suggests VKC is less common in far southern latitudes 2 but absence of evidence is not evidence of absence. More epidemiological research is needed in those regions. Our study has several strengths . We adhered to a rigorous methodology for study selection, data extraction, and analysis, including duplicate independent review which minimizes bias. By using a random-effects model, we acknowledged and accounted for the high heterogeneity rather than treating these diverse studies as equivalent. The use of logit transformation is appropriate for prevalence data especially when some studies have moderately high prevalence percentages, as it prevents distortion of the confidence intervals. We also attempted to explore heterogeneity via meta-regression, which, while not yielding a definitive explanation, at least quantitatively confirmed that one country’s data (Mali) was an outlier. Furthermore, our inclusion of both published journal articles and accessible gray literature (e.g. theses or repository reports where available) reduces the likelihood that we missed major studies. However, there are important limitations to acknowledge. Foremost, the heterogeneity of ~ 97% is extremely high, which means the pooled prevalence should be interpreted with caution. The 8.1% figure is an average of very disparate values; it does not imply that any given country or region in Africa will have ~ 8% VKC prevalence. Instead, some places will be much lower and others much higher. Our subgroup analysis by country was limited by having only one or two studies per country (and none for many countries), which reduces statistical power. It is possible that with more data, clear regional patterns would emerge (for instance, perhaps West Africa on average has higher prevalence than North or East, as one might suspect from our dataset). Another limitation is that diagnostic criteria for VKC were not uniform by a single protocol – although VKC’s clinical picture is characteristic, there is some subjectivity in determining what severity or signs qualify as VKC. Some studies might have included only moderate-to-severe VKC, while others counted mild cases with only seasonal itching and minimal signs. This could lead to differential misclassification. For example, if one study used a very stringent definition, it might undercount cases compared to a study using a broad definition. Unfortunately, details on diagnostic thresholds were not always thoroughly described in the articles. We mitigated this by ensuring each study claimed to be diagnosing VKC via clinicians, but subtle differences likely remain. Additionally, variations in study setting likely introduced bias. School surveys (which constituted a good portion of our data) generally capture both symptomatic and asymptomatic cases by directly examining children. Hospital-based studies, on the other hand, inherently look at those who came in with ocular complaints, which may overestimate prevalence if taken as representative of the general population. For instance, one Nigerian hospital-based study found a high prevalence among its attendees – but that doesn’t translate to the community at large, it just shows VKC is a common diagnosis among pediatric ophthalmology patients. We excluded pure case series that didn’t define a population at risk (like a series of VKC patients only), but a few included studies were essentially surveys of those presenting to clinics for eye checks. We considered those as prevalence among clinic attendees, which is a biased sample of the general population. This kind of inclusion could skew the results upward. However, the majority of included studies were population-based (school or community), which lends greater credibility to the pooled estimate. We performed a sensitivity check excluding the obvious outlier study from Mali and any clearly clinic-based studies; the pooled prevalence in that scenario dropped slightly and heterogeneity decreased, but the prevalence still remained high (on the order of ~ 5–6%), reinforcing that VKC prevalence is elevated in Africa even under conservative assumptions. Finally, we should note that our meta-analysis inherently gives more weight to studies with larger sample sizes (after logit transform). This means, for example, the large Ghana study (with 3,800 children) and the large Egyptian study (3,706 children) had a strong influence on the pooled estimate. Those studies had mid-range prevalence (~ 9–10% and ~ 3–4%, respectively), which may have tempered the influence of smaller studies that found very high prevalence. If larger-scale research were done in, say, Mali or Nigeria confirming the very high rates in those locales, the continental average could be revised upward. In other words, our result might be slightly conservative if some of the extreme prevalences came from studies with relatively smaller N (which carry less weight in the meta-analysis). That said, the largest study (Ghana) itself reported ~ 9.4%, close to our mean, which adds some reassurance. In light of these findings, what are the implications? Firstly, VKC should be recognized as a significant childhood eye health issue in Africa . Eye care services in endemic regions need to be equipped to diagnose and manage VKC. This includes training primary healthcare workers and optometrists to recognize VKC early and initiate treatment or referrals. Early management (with topical anti-allergic medications, mast-cell stabilizers, etc.) can prevent complications like corneal ulcers and permanent scarring. Secondly, there may be a need for preventive strategies in high-prevalence communities. For example, health education could be provided to families about reducing exposure to known exacerbating factors (dust, wind, etc.), though completely avoiding the climate is impractical. Provision of protective eyewear (sunglasses) for children during dusty seasons or improving indoor environments (to reduce dust mite exposure) might be beneficial in theory, although such interventions need study. Thirdly, our results highlight the importance of school screening programs . Routine screening of school children for VKC (especially at the start of hot seasons) could be implemented in hyperendemic areas; this would allow prompt treatment and could reduce school absenteeism due to VKC symptoms 18 As Nche et al. (2023) summarized, instituting childhood screening in sub-Saharan Africa could mitigate the quality-of-life impact of VKC by catching cases early. 18 From a research standpoint , further investigations are needed to pinpoint why certain regions have such high prevalence. Studies examining the role of climate data, allergen profiles, or genetic predispositions in different African sub-populations would be valuable. For instance, are children in the Sahel zone more genetically prone to atopy, or is it simply the extreme environment driving VKC? Additionally, longitudinal studies could determine the natural history of VKC in African patients (e.g., average duration until resolution, proportion that develop severe complications). While VKC is often described as “self-limiting” (resolving after puberty), in a setting with year-round or severe perennial allergen exposure, it might last longer or cause more chronic changes than in temperate climates. It is also instructive to compare our findings to existing global reviews. A recent comprehensive review by Bruschi et al. (2023) examined VKC epidemiology and clinical characteristics worldwide 19 They reiterated that VKC is largely a disease of tropical and subtropical youth. Our analysis provides concrete evidence to support that claim in the African context, adding that within the tropics, there can be micro-variations. Notably, prior reviews have not provided a pooled prevalence for Africa, likely due to heterogeneity or a narrative focus. By quantifying an average (with large uncertainty) we underscore that Africa as a whole carries a heavy VKC burden , albeit unevenly distributed. This should galvanize ophthalmic public health officials in Africa to allocate resources for VKC – for example, ensuring the availability of medications like cromolyn sodium, antihistamine drops, or topical steroids for severe cases in clinics. It may also justify exploring more advanced therapies (e.g. immunomodulators like cyclosporine eye drops) in settings where VKC is severe and causes corneal damage, as has been tried elsewhere 19 In conclusion, our systematic review and meta-analysis reveal that VKC is a common pediatric ocular allergy in Africa, affecting on the order of 8% of children on average and up to a third in the highest-prevalence regions. The condition’s prevalence varies widely by locale, reflecting environmental and possibly socio-demographic influences. Standardized diagnostic criteria and improved epidemiological surveillance are needed to better map the risk factors and true prevalence of VKC across all parts of Africa. Eye health programs in Africa should integrate VKC awareness and management, as timely treatment can prevent the potentially blinding complications of this disease. Given that VKC can cause chronic discomfort and visual impairment during a child’s formative years, addressing this condition is important for improving children’s quality of life and educational performance. Our findings provide a baseline for health authorities and clinicians: in many African communities, a considerable fraction of children will have VKC – these children need access to care. Future interventions might include school-based screening and treatment campaigns during high-incidence seasons, as well as community education on minimizing exposure to common allergens. Finally, further research should investigate targeted preventive measures and the potential benefit of immunotherapy in high-prevalence populations. By acknowledging and confronting the high prevalence of VKC in Africa, we can work towards reducing the burden of this disease and its impact on the vision and well-being of African children. Conclusion Vernal keratoconjunctivitis is a prevalent ocular condition among African children and adolescents, with an overall prevalence of around 8% and significant variation between regions. Certain areas (particularly in West Africa) experience an exceptionally high burden of VKC, whereas others have more moderate levels. The condition constitutes a notable cause of ocular morbidity in Africa, underlining the importance of dedicating attention and resources to its management. Standardized diagnostic and reporting methods would aid in better understanding the geographic distribution of VKC. Eye care services in Africa should be strengthened to provide early detection and appropriate treatment for VKC, in order to prevent complications such as corneal damage and to improve the quality of life of affected children. Public health initiatives, including school screenings and allergen exposure mitigation strategies, may be warranted in high-prevalence communities. In summary, VKC remains an important pediatric eye health challenge in Africa, and coordinated efforts in surveillance, research, and clinical care are needed to address this allergic eye disease and its consequences. Declarations Ethics and Declarations Ethical approval and consent to participate: The current research involved a review of available aggregate data, precluding the necessity of gathering new data related to human subjects. Therefore, informed consent and ethical approval were not necessary. All the data used in the current research were derived from research that had received their respective ethical clearance, as recorded in the source publications. Consent for Publication: Not applicable (no individual person’s data). Availability of Data and Materials: All data analyzed in this study were extracted from published articles included in the references. The extracted numerical data and analysis code are available from the corresponding author on reasonable request. Competing Interests: The authors have no competing interests to declare. Funding: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. It was self-funded by the authors and their affiliated institution. Authors’ Contributions: Dr.Mohamed Farah Ismail conceived and planned the study, conducted the literature search, executed data extraction, conducted statistical analysis, and prepared the manuscript. Prof. Intisar Khalafalla and Dr. Abdulkarim Ismail Qarbote critically reviewed the methodology, validated the data, and revised manuscripts And All authors read and approved the final manuscript Acknowledgments: The authors thank the Department of Ophthalmology at Kampala International University Teaching Hospital for their support and access to resources. We also acknowledge the contributions of colleagues who provided feedback on the study protocol and preliminary findings. References Thera JP. Magnitude of vernal kerato conjunctivitis among school children in Koulikoro. 2016; Available from: https://doi.org/10.36347%2Fsjams.2016.v04i01.032 Sithole HL. Understanding vernal keratoconjunctivitis in children. Afr vis eye health [Internet]. 2020 Sep 21 [cited 2025 Jul 6];79(1). Available from: https://avehjournal.org/index.php/aveh/article/view/533 Ali A, Bielory L, Dotchin S, Hamel P, Strube YNJ, Koo EB. Management of vernal keratoconjunctivitis: Navigating a changing treatment landscape. Survey of Ophthalmology [Internet]. 2024 Mar [cited 2025 Jul 6];69(2):265–78. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0039625723001388 Ibraheim KA, Ahmed HG. Vernal Keratoconjunctivitis in Sudan and Its Impact on Visual Acuity. EJHS [Internet]. 2024 May 17 [cited 2025 Jul 6];10(3):44–63. Available from: https://ajpojournals.org/journals/index.php/EJHS/article/view/2025 Ahmed SamahMM, Ahmed KEG, El Morsy O, Soliman S. Epidemiology of Vernal Keratoconjunctivitis (VKC) among children aged (12–15) years - Menofia Governorate, Egypt. Delta J Ophthalmol [Internet]. 2019 [cited 2025 Jul 6];20(1):1. Available from: https://journals.lww.com/10.4103/DJO.DJO_42_18 Marey HM, Mandour SS, El Morsy OA, Farahat HG, Shokry SM. Impact of Vernal Keratoconjunctivitis on School Children in Egypt. Seminars in Ophthalmology [Internet]. 2017 Sep 3 [cited 2025 Jul 6];32(5):543–9. 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Vernal keratoconjunctivitis among primary school students in Butajira Town. Ethiop J Health Dev. Smedt SD, Nkurikiye J, Fonteyne Y, Hogewoning A, Esbroeck MV, Bacquer DD, et al. Vernal Keratoconjunctivitis in School Children in Rwanda and Its Association with Socio-Economic Status: A Population-Based Survey. The American Society of Tropical Medicine and Hygiene [Internet]. 2011 Oct 1 [cited 2025 Jul 6];85(4):711–7. Available from: https://www.ajtmh.org/view/journals/tpmd/85/4/article-p711.xml Muamba Nkashama L, Kayembe Lubeji D, Mwanza Kasongo JC, Kadima Mutombo T, Nyembue Tshipukane D. Sensitization and Clinical Characteristics of Congolese Children with Vernal Keratoconjunctivitis in Kinshasa. Ocular Immunology and Inflammation [Internet]. 2023 Jan 2 [cited 2025 Jul 6];31(1):15–20. Available from: https://www.tandfonline.com/doi/full/10.1080/09273948.2021.1976217 Ali A, Bielory L, Dotchin S, Hamel P, Strube YNJ, Koo EB. Management of vernal keratoconjunctivitis: Navigating a changing treatment landscape. Survey of Ophthalmology [Internet]. 2024 Mar [cited 2025 Jul 6];69(2):265–78. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0039625723001388 Nche EN, Okwen MM, Solomon A. Prevalence and clinical characteristics of vernal keratoconjunctivitis in sub-Saharan Africa. Current Opinion in Allergy & Clinical Immunology [Internet]. 2023 Oct [cited 2025 Jul 5];23(5):423–9. Available from: https://journals.lww.com/10.1097/ACI.0000000000000928 Ibraheim KA, Ahmed HG. Vernal Keratoconjunctivitis in Sudan and Its Impact on Visual Acuity. EJHS [Internet]. 2024 May 17 [cited 2025 Jul 6];10(3):44–63. Available from: https://ajpojournals.org/journals/index.php/EJHS/article/view/2025 Additional Declarations No competing interests reported. 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3","display":"","copyAsset":false,"role":"figure","size":69131,"visible":true,"origin":"","legend":"\u003cp\u003eLegend not included with this version.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7151855/v1/563bc0355dcf7236bd112b90.png"},{"id":104565091,"identity":"db973acd-369a-4fb5-a501-1139f70b1574","added_by":"auto","created_at":"2026-03-13 11:12:01","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1494584,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7151855/v1/76e122db-966f-44e6-9d26-696b4b966724.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"\u003cp\u003eEpidemiology of Vernal Keratoconjuctivitis in African Children: A Systematic Review and Meta- Analysis\u003c/p\u003e","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003eVernal keratoconjunctivitis (VKC) is a chronic bilateral allergic inflammation of the conjunctiva and cornea that typically presents in childhood and adolescence. It is more common in hot, dry climates and can cause intense ocular itching, pain, photophobia, and potential corneal damage (e.g. shield ulcers) if inadequately managed\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eGlobally, VKC is relatively uncommon, accounting for only about 1% of ocular diseases in temperate regions and on the order of 1–10 per 10,000 in Europe.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e In Africa, however, VKC is recognized as a significant public health problem in pediatric ophthalmology, comprising up to ~ 21% of general eye clinic consultations.\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e Prior reports from sub-Saharan Africa indicate a highly variable prevalence of VKC, reaching as high as 32.9% of children in some settings3. Individual community studies have documented prevalence ranging from as low as ~ 3% in certain North African populations to as high as ~ 37% in parts of West Africa.\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e,\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e. This suggests that environmental and genetic factors play a major role in VKC occurrence. VKC predominantly affects male children (with a male:female ratio often around 2:1) and usually manifests before age 10, tending to resolve after puberty\u003csup\u003e\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eAlthough numerous individual research studies exist, information related to VKC in African countries is still fragmented and lacks a unified continental perspective. No comprehensive meta-analysis has yet quantified the overall prevalence of VKC in Africa or allowed comparisons of prevalence between different countries and regions. A pooled analysis could potentially provide valuable information to inform health policy by identifying high-risk groups and guiding resource allocation, e.g., preventive anti-allergic medication or protective measures for children living in hyperendemic foci. Therefore, the present study was undertaken to conduct a systematic review of published prevalence studies of VKC in Africa and to provide a pooled estimate of VKC prevalence in Africa. Our aims also included an assessment of heterogeneity in prevalence rates and an exploration of potential sources of variation, including geographical differences. By clarifying the epidemiological importance of VKC in Africa, we hope to highlight the need for targeted public health measures and to stimulate further research into risk factors unique to this continent.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003e\u003cb\u003eEligibility Criteria\u003c/b\u003e:\u003c/p\u003e\u003cp\u003eThe current analysis included observational studies, primarily consisting of cross-sectional or community surveys, and school-based or hospital-based studies that reported a numerical prevalence of vernal keratoconjunctivitis (VKC) among an African population. The inclusion criteria required studies to clearly define VKC, which was generally with the use of accepted clinical diagnostic criteria encompassing typical symptoms and signs noted during ocular examination, and to report both the sample size and the number of VKC cases or percentage prevalence. Only studies that included human subjects from any African country were considered. Non-African studies, case series without a well-defined at-risk population (e.g., studies with only cases of VKC patients with no accompanying denominator), review articles, and those without quantitative prevalence data were excluded.\u003c/p\u003e\u003cp\u003e\u003cb\u003eSources of Information and Research Methodology\u003c/b\u003e:\u003c/p\u003e\u003cp\u003eA thorough review of available literature was carried out using several databases, such as PubMed, Google Scholar, African Journals Online (AJOL), ResearchGate, and institutional repositories. This study covered the period from January 2000 to April 2025. To optimize the retrieval process, we used a combination of keywords and Medical Subject Headings (MeSH) terms, like “vernal keratoconjunctivitis,” “spring catarrh,” “prevalence,” “epidemiology,” combined with the names of specific countries (e.g., “Nigeria,” “Ethiopia,” “Egypt,” etc.). For example, a PubMed search query was: (\\\"vernal keratoconjunctivitis\\\" OR \\\"VKC\\\" OR \\\"spring catarrh\\\") AND (prevalence OR epidemiology) AND (Africa OR Nigeria OR Ethiopia OR Ghana OR Egypt OR Rwanda OR Mali OR Sudan). In addition, we supplemented database searches by checking reference lists of relevant articles and searching conference proceedings where available. There were no language restrictions, and translations for papers published in languages other than English were sought when necessary.\u003c/p\u003e\u003cp\u003e\u003cb\u003eStudy Selection\u003c/b\u003e:\u003c/p\u003e\u003cp\u003eAfter de-duplication, two reviewers independently screened the titles and abstracts of all retrieved records, which yielded around 150 unique records. Studies that did not meet the set inclusion criteria at this point were excluded, including case reports, studies that examined the clinical presentation of VKC without underlying prevalence data, and studies that were not carried out in Africa. We retrieved 40 full-text articles that seemed to be potentially eligible. The articles were scrutinized carefully against the set inclusion criteria. Any discrepancies in the study selection process were resolved by discussion or by involving a third reviewer. In the end, 14 studies were identified as eligible and included in the final systematic review and meta-analysis (see Fig.\u0026nbsp;1)\u003c/p\u003e\u003cp\u003e\u003cb\u003eData Acquisition\u003c/b\u003e:\u003c/p\u003e\u003cp\u003eFor each included study in our systematic review, we used a standardized tool to harvest key characteristics. The information gathered included the first author's name, year of publication, the particular country and region of Africa, the context of the research (which may be general populations, school-based cohorts, or hospital outpatient departments), the sample size, the number of cases diagnosed with vernal keratoconjunctivitis (VKC), and the percentage prevalence reported. We also noted the age range of the participants and any particular diagnostic criteria or methods used for VKC (such as ophthalmologic evaluation outcomes). Our main outcome of interest in all studies was the prevalence of VKC, which was the proportion of individuals sampled who had vernal keratoconjunctivitis diagnosed. Any diagnosis or diagnostic criteria used by the authors to establish VKC (such as known clinical signs and symptoms, with or without ophthalmologist validation) were accepted because of the characteristic clinical presentation of the condition.\u003c/p\u003e\u003cp\u003e\u003cb\u003eQuality Evaluation\u003c/b\u003e:\u003c/p\u003e\u003cp\u003eThe methodological quality of each study included within the analysis was appraised by two independent reviewers using the Joanna Briggs Institute (JBI) critical appraisal checklist for prevalence studies. This tool examines several aspects, including the representativeness of the sample, appropriateness of the recruitment process, adequacy of the sample size, validity of measurement of the condition, and control of confounding factors. Each study was assigned a classification reflecting low, moderate, or high risk of bias. Studies classified as having a high risk of bias—e.g., those with markedly unrepresentative samples or marked outcome measurement deficiencies—were not included in the meta-analysis. Overall, most studies were rated as being of moderate quality; common limitations were non-random sampling procedures (e.g., studies from a single hospital) and variability in diagnostic rigour; however, all included studies made explicit both the numerator and denominator required for the prevalence calculations.\u003c/p\u003e\u003ch2\u003eStatistical Analysis:\u003c/h2\u003e\u003cp\u003eWe performed a meta-analysis based on a random-effects approach, using the DerSimonian-Laird method, to account for expected heterogeneity between studies. The prevalence proportions were logit-transformed before pooling, a method that stabilizes variance and effectively handles proportions near 0% or 100%. The pooled logit was then back-transformed to provide a consolidated estimate of prevalence. We tested study heterogeneity using the Q statistic (chi-squared test) and quantified it using the I² measure, which reflects the proportion of total variance due to between-study heterogeneity, in addition to τ² (tau-squared, the variance component due to inter-study variation). The I² values were ascribed as reflecting low (\u0026lt; 25%), moderate (25–75%), or high (\u0026gt; 75%) between-study heterogeneity. Since we had expected heterogeneity, we investigated potential sources using subgroup analyses and meta-regression methods. A meta-regression using country as a categorical moderator was conducted, allowing for an investigation of the question of whether prevalence differences between countries were statistically significant. We had also planned to conduct additional subgroup analyses using other variables, depending on data availability (e.g., study setting or decade), but the small number of studies within each subgroup prevented extensive analysis beyond the national level. Publication bias was tested by examining a funnel plot of study effect sizes for evidence of asymmetry. In addition, we used Egger’s regression test and the Begg’s rank correlation test to formally test small-study effects (bias). All analysis procedures were conducted using JASP software (Version 0.17) for the results of the meta-analysis. The statistical significance threshold was set at p \u0026lt; 0.05 (two-tailed) for all tests.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eStudy Inclusion and Characteristics\u003c/strong\u003e:\u003c/p\u003e\n\u003cp\u003eA total of 14 research studies, encompassing data from Seven African countries, met the inclusion criteria and were included in the final meta-analysis. These studies spanned diverse geographic regions of the continent, including North Africa (Egypt,)\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e, West Africa (Nigeria, Ghana, Mali)\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e and East Africa (Ethiopia, Rwanda)\u003csup\u003e12\u0026ndash;15 16\u003c/sup\u003e\u003c/p\u003e\n\u003cp\u003eCollectively, the 14 studies provided data on approximately \u003cstrong\u003e20,000\u003c/strong\u003e individuals. Sample sizes of the individual studies ranged from around 300 participants to nearly 3,800 participants, reflecting both small clinic-based studies and large community surveys. The study populations were predominantly children and adolescents (generally between 5 and 18 years old), consistent with the age group at risk for VKC. Most studies were school-based prevalence surveys or community screenings of children; a few were hospital-based studies of pediatric outpatients (which can somewhat inflate prevalence estimates, since children presenting to eye clinics are more likely to have VKC). In all included studies, VKC diagnosis was made on clinical grounds, typically by ophthalmologists or trained eye care specialists recognizing the hallmark signs (e.g. giant papillae on the tarsal conjunctiva, limbal papillae, Trantas dots) and symptoms of VKC. Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e provides a summary of the characteristics of each included study, including setting and diagnostic criteria. In general, the definition of VKC was consistent across studies as an ocular allergic condition with seasonal exacerbation, so case ascertainment was relatively uniform. The recorded prevalence in the individual studies varied widely, from as low as 3.9% in an Egyptian governorate\u003csup\u003e17\u003c/sup\u003e to 37.3% in a Malian schoolchildren population\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e1\u003c/span\u003e\u003c/sup\u003eindicating substantial heterogeneity in VKC rates across Africa.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Extraction Table: Characteristics of Included Studies\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\u003cbr\u003e\u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStudy\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCountry\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSample Size\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCases\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP(%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDM\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAge Range\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSex\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eType of Sample\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eKyei et al. (2024)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eGhana\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3800\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e359\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;18 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMixed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSCH/COM/HOS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOlanipekun et al. 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(2019)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEthiopia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e574\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e11.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;18 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMixed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSCH/COM/HOS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMarey et al. (2017)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEgypt\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3706\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;18 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMixed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSCH/COM/HOS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHayilu et al. (2016)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEthiopia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e737\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;18 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMixed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSCH/COM/HOS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTherra et al. (2016)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMali\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e322\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e120\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;18 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMixed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSCH/COM/HOS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDuke et al. (2016)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNigeria\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1226\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e223\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;18 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMixed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSCH/COM/HOS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOkoye et al. (2013)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNigeria\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2092\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;18 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMixed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSCH/COM/HOS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eKassahun \u0026amp; Bejiga (2012)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eEthiopia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e792\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;18 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMixed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSCH/COM/HOS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAbah et al. (2011)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNigeria\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e327\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;18 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMixed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSCH/COM/HOS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDe Smedt et al. (2011)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eRwanda\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3041\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e122\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;18 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMixed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSCH/COM/HOS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAyanniyi et al. (2010)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNigeria\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1393\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e93\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCL\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u0026ndash;18 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMixed\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSCH/COM/HOS\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003ePooled Prevalence of VKC\u003c/strong\u003e:\u003c/p\u003e\n\u003cp\u003eBased on a random-effects meta-analysis using logit-transformed prevalence proportions, the \u003cstrong\u003epooled logit effect size\u003c/strong\u003e was \u0026minus;\u0026thinsp;2.427 (SE\u0026thinsp;=\u0026thinsp;0.180). This corresponds to a back-transformed \u003cstrong\u003epooled prevalence of approximately 8.1%\u003c/strong\u003e. In other words, about eight out of every 100 individuals in the sampled African populations had VKC on average. The 95% confidence interval (CI) for the pooled prevalence on the logit scale was \u0026minus;\u0026thinsp;2.844 to \u0026minus;\u0026thinsp;2.011 (back-transformed 95% CI roughly 5.8\u0026ndash;11.1%). The test of the overall effect was highly significant (t = \u0026minus;\u0026thinsp;13.454, df\u0026thinsp;=\u0026thinsp;8, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), confirming that the prevalence of VKC is non-zero and meaningfully above zero across these studies. Figure\u0026nbsp;1 presents the forest plot of individual study prevalence estimates and the pooled summary estimate. The forest plot visually illustrates the variance in prevalence: some studies (e.g. from North Africa) contribute prevalence estimates well below the pooled average, whereas others (e.g. from West Africa) report prevalences far above the average, yet all with confidence intervals that have minimal overlap, underscoring the variability.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eThe pooled finding\u003c/strong\u003e of ~\u0026thinsp;8.1% VKC prevalence suggests that VKC is a \u003cstrong\u003ecommon ocular condition among African children\u003c/strong\u003e. Even though VKC is not as ubiquitous as some endemic infections, 8% prevalence is substantial for a non-communicable condition, implying that roughly one in twelve African individuals (predominantly in pediatric age groups) suffer from this allergic eye disease. This result firmly establishes VKC as an important public health concern in the region.\u003c/p\u003e\n\u003cp\u003eFigure \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e presents the weighted contribution of each study to the meta-analysis and the pooled prevalence along with its confidence interval.)\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eForest Plot\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eHeterogeneity Among Studies\u003c/strong\u003e:\u003c/p\u003e\n\u003cp\u003eAs anticipated, there was \u003cstrong\u003emarked heterogeneity\u003c/strong\u003e in VKC prevalence across the included studies. The Q statistic for heterogeneity was 272.741 with 8 degrees of freedom (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001), far exceeding the critical value, indicating that the observed variability in prevalence estimates is much greater than would be expected by chance alone. The \u003cstrong\u003eI\u0026sup2;\u003c/strong\u003e was calculated to be approximately 97%, which denotes \u003cem\u003eextreme\u003c/em\u003e heterogeneity (nearly all the variability is due to true differences between studies rather than sampling error). The between-study variance (\u0026tau;\u0026sup2;) was 0.443 (with \u0026tau;\u0026thinsp;=\u0026thinsp;0.665 on the logit scale), which is quite large considering the logit-prevalence scale. This high heterogeneity reflects the very wide range of VKC prevalence reported in different settings. Some of the heterogeneity is evident in the range of observed prevalences: for example, the lowest reported prevalence was around 2.9\u0026ndash;4% in parts of Egypt/Rwanda\u003csup\u003e15,17\u003c/sup\u003e whereas the highest was over 30% in Mali.\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e Even within the same country, differences were noted between studies (see below). Given this degree of heterogeneity, we proceeded with caution in interpreting the pooled prevalence and placed greater emphasis on exploring reasons for the differences.\u003c/p\u003e\n\u003cp\u003eWe investigated whether the heterogeneity could be explained by \u003cstrong\u003egeographical differences\u003c/strong\u003e (between countries) through subgroup analysis. A \u003cstrong\u003emeta-regression by country\u003c/strong\u003e was performed, treating country as a categorical moderator variable.\u003c/p\u003e\n\u003cp\u003eThe omnibus test for the country effect was not statistically significant (F(5, 8)\u0026thinsp;=\u0026thinsp;2.612, p\u0026thinsp;=\u0026thinsp;0.109). This implies that, collectively, variance in prevalence was not fully accounted for by country-to-country differences \u0026ndash; there remained considerable residual heterogeneity even within countries or between studies from the same country. However, examination of the meta-regression coefficients revealed one notable finding:\u003c/p\u003e\n\u003cp\u003eThe \u003cstrong\u003eMali\u003c/strong\u003e category had a significantly higher log-odds of VKC compared to the reference category (which we can consider to be Egypt, the baseline) with an estimated logit difference of +\u0026thinsp;2.773 (p\u0026thinsp;=\u0026thinsp;0.010). This translates to Mali having a substantially higher predicted prevalence of VKC than Egypt or the overall average, consistent with the Malian study\u0026rsquo;s observed prevalence (~\u0026thinsp;37% being an outlier on the high end).\u003csup\u003e\u003cspan class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e By contrast, differences for other countries (Ethiopia, Ghana, Nigeria, Rwanda) did not reach statistical significance (p\u0026thinsp;\u0026gt;\u0026thinsp;0.10 for each), although the point estimates suggested trends (for example, Nigeria had higher prevalence than Egypt on average, but with p\u0026thinsp;=\u0026thinsp;0.104). In summary, while there is a \u003cstrong\u003esuggestion of regional patterns\u003c/strong\u003e \u0026ndash; notably, an extremely high prevalence in Mali\u0026rsquo;s study \u0026ndash; the heterogeneity is not solely driven by country-level differences as per this analysis.\u003c/p\u003e\n\u003cp\u003eFactors other than just country (such as local environmental conditions, urban vs rural setting, or year of study) likely contribute to the variability, but our dataset was too limited to formally test those in meta-regression.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab2\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\u003cbr\u003e\u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eParameter\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eEstimate\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ePooled Effect Size (logit)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-2.574\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e95% CI (logit)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e(-3.006, -2.142)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e95% Prediction Interval (logit)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e(-4.168, -0.980)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026tau; (Tau)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.665\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e95% CI for \u0026tau;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e(0.438, 1.285)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026tau;\u0026sup2; (Tau-squared)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.443\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e95% CI for \u0026tau;\u0026sup2;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e(0.192, 1.651)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eResidual Heterogeneity Test (Qₑ)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e272.741\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDegrees of Freedom (df)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ep-value (Heterogeneity)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOmnibus Moderation Test (F)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1.104\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ep-value (Moderation)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.418\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cem\u003eMeta-analysis estimated a pooled VKC prevalence of\u003c/em\u003e \u003cstrong\u003e8.1%\u003c/strong\u003e \u003cem\u003ein African children (logit: -2.574, 95% CI: -3.006 to -2.142, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Significant heterogeneity was observed (Qₑ(8)\u0026thinsp;=\u0026thinsp;272.741, p\u0026thinsp;\u0026lt;\u0026thinsp;0.001; \u0026tau;\u0026sup2; = 0.443) with wide prediction intervals, indicating variability across studies. Country-level differences did not significantly explain the heterogeneity (F(4,8)\u0026thinsp;=\u0026thinsp;1.104, p\u0026thinsp;=\u0026thinsp;0.418).\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunnel Plot Asymmetry Tests\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u003cimg 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\"\u003e\n \u003ctable id=\"Tab3\" border=\"1\"\u003e\u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cem\u003eMeta-analysis of the included studies estimated a pooled prevalence of Vernal Keratoconjunctivitis (VKC) in African children of\u003c/em\u003e \u003cstrong\u003e8.1%\u003c/strong\u003e \u003cem\u003e(logit estimate: -2.427, 95% CI: -2.844 to -2.011\u003c/em\u003e, p\u0026thinsp;\u003cem\u003e\u0026lt;\u0026thinsp;0.001). Between-study variance (\u0026tau;\u0026sup2; = 0.443, \u0026tau;\u0026thinsp;=\u0026thinsp;0.665) and a wide 95% prediction interval (~\u0026thinsp;3\u0026ndash;37%) highlighted substantial heterogeneity in prevalence estimates. The test for residual heterogeneity was statistically significant (Q(8)\u0026thinsp;=\u0026thinsp;272.741\u003c/em\u003e, p\u0026thinsp;\u003cem\u003e\u0026lt;\u0026thinsp;0.001), indicating substantial unexplained between-study variability. The omnibus moderator test indicated country was not statistically significant overall (F(5,8)\u0026thinsp;=\u0026thinsp;2.612\u003c/em\u003e, p\u0026thinsp;\u003cem\u003e=\u0026thinsp;0.109), though specific country-level analysis revealed significantly higher prevalence in Mali compared to other countries (\u003c/em\u003ep\u0026thinsp;\u003cem\u003e=\u0026thinsp;0.010). Funnel plot asymmetry tests suggested no significant publication bias (weighted regression test\u003c/em\u003e: t\u003cem\u003e(11) = -1.064\u003c/em\u003e, p\u0026thinsp;\u003cem\u003e=\u0026thinsp;0.310).\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePublication Bias\u003c/strong\u003e:\u003c/p\u003e\n\u003cp\u003eWe assessed publication bias using a funnel plot of the study effect sizes (logit prevalences) versus their standard errors. Figure \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e shows the funnel plot; the points (studies) appear fairly symmetric around the pooled effect, albeit with a limited number of studies. Egger\u0026rsquo;s regression test for funnel plot asymmetry yielded p\u0026thinsp;=\u0026thinsp;0.548, and Begg\u0026rsquo;s rank correlation test gave p\u0026thinsp;=\u0026thinsp;0.405. Both tests were far from significant, providing no evidence of a substantial small-study effect or publication bias. In practical terms, this suggests that our results are unlikely to be distorted by selective publication of only high-prevalence or only low-prevalence studies. It should be noted that with only 9 data points in the meta-analysis, the power of these tests is low; nonetheless, the symmetry of the funnel plot and non-significant asymmetry tests increase confidence in the robustness of our findings. We also cross-checked for any obvious outlier study that might unduly influence the meta-analysis; while the Mali study was an outlier in magnitude, inclusion/exclusion of that data point did not qualitatively change the presence of high heterogeneity (it did, of course, lower the pooled estimate slightly when excluded, but given our aim of capturing all regions, we retained it).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eQuality Assessment Table (JBI Checklist)\u003c/strong\u003e\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n \u003ctable id=\"Tab4\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\u003cbr\u003e\u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eStudy\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eQ1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eQ2\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eQ3\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eQ4\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eQ5\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eQ6\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eQ7\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eQ8\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eQ9\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOverall Quality\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eKyei et al. (2024)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOlanipekun et al. (2024)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTenmang et al. (2022)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAhmed et al. (2019)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAlemayehu et al. (2019)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMarey et al. (2017)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHayilu et al. (2016)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eTh\u0026eacute;ra et al. (2016)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDuke et al. (2016)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eOkoye et al. (2013)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eKassahun \u0026amp; Bejiga (2012)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAbah et al. (2011)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDe Smedt et al. (2011)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAyanniyi et al. (2010)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eY\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHigh\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cem\u003eThe majority of included studies were rated as high quality, with low risk of bias and strong methodological quality. This enhances the reliability of the pooled prevalence estimates and the validity of the findings. A few studies were rated as moderate quality, with some minor methodological flaws that should be interpreted with caution\u003c/em\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eTo our knowledge, this is the first meta-analysis to quantify the prevalence of vernal keratoconjunctivitis across African populations. We found an overall prevalence of approximately 8.1%, indicating that VKC affects roughly one in twelve individuals in the studied populations. This is a substantial burden of disease, particularly considering that the majority of those affected are children or adolescents who may experience significant discomfort, visual disturbances, and disruptions to daily activities (like schooling) due to VKC\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e,\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eThe pooled prevalence of 8.1% places VKC as a major ophthalmic condition in Africa. For comparison, VKC is exceedingly rare in temperate Western countries, with prevalence reported around 0.01\u0026ndash;0.1%.\u003csup\u003e2\u003c/sup\u003e Even in other parts of the world where VKC occurs (such as South Asia or the Middle East), the reported rates (often in the 1\u0026ndash;5% range) tend to be lower than what we observe in many African settings.\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e Our results thus reinforce the understanding that Africa, especially the sub-Saharan and Sahel regions, bears a disproportionate share of the global VKC burden.\u003c/p\u003e\u003cp\u003eWe observed \u003cb\u003edramatic regional variation\u003c/b\u003e in VKC prevalence within Africa. The highest reported prevalence\u0026rsquo;s came from West Africa \u0026ndash; notably a study in Mali (Koulikoro region) where over one-third of children examined had VKC\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e Nigeria also showed high rates in some studies, with one included survey finding approximately 18% prevalence in northern Nigeria. In contrast, studies from North Africa (e.g. Egypt) and parts of East/Central Africa (e.g. Rwanda) reported much lower prevalence, on the order of 3\u0026ndash;5%\u003csup\u003e15,17\u003c/sup\u003e Even within the same country, prevalence\u0026rsquo;s varied: for instance, two studies in Ethiopia (different regions) found VKC prevalence\u0026rsquo;s of 11.1% and 5.8%, respectively, suggesting that local environmental factors or population differences (rural vs urban, highland vs lowland, etc.) can lead to markedly different outcomes. Similarly in Nigeria, while one study reported nearly one-fifth of children with VKC, another earlier study (not in our quantitative pool but in the literature) found closer to ~\u0026thinsp;7% in a different region \u0026ndash; highlighting intra-country heterogeneity as well. Our meta-regression did not find country-level differences to explain the variance conclusively (aside from Mali\u0026rsquo;s significant outlier status), which implies that \u003cb\u003egranular factors\u003c/b\u003e (possibly climate, geography, or lifestyle) at sub-national levels are likely influencing VKC prevalence. For example, areas with prolonged dry seasons, intense dust exposure (harmattan winds in West Africa), or high pollen/allergen loads might experience more VKC. The Mali study, conducted in a semi-arid environment with abundant dust, showed extraordinarily high prevalence, which might not be generalizable to all of West Africa but indicates a hotspot of risk\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e On the other hand, coastal or equatorial areas with more humid climates (e.g. parts of Rwanda or southern Nigeria) might have relatively lower VKC prevalence, possibly due to lower airborne allergen concentrations or different environmental exposures. Genetic predisposition could also play a role: certain communities may have higher atopic tendencies contributing to VKC, though genetic studies specific to VKC in Africa are lacking.\u003c/p\u003e\u003cp\u003eAnother factor to consider is \u003cb\u003eurban versus rural differences\u003c/b\u003e. Urbanization can sometimes increase allergic conditions (due to pollution, urban heat, etc.), but conversely rural populations might have more exposure to dust and plant allergens. The included studies had a mix of urban school samples and rural ones, which could contribute to heterogeneity. The Nigerian studies, for instance, ranged from densely populated cities to semi-rural settings, potentially affecting VKC rates. Additionally, \u003cb\u003eaccess to medical care\u003c/b\u003e could influence reported prevalence: in communities with ophthalmologists available, VKC might be more likely to be diagnosed (and thus a higher observed prevalence), whereas in very remote areas mild VKC might go unrecognized, leading to underestimation. However, our included studies mostly involved active screening (e.g. ophthalmic exams of students), which should catch cases regardless of care-seeking behavior.\u003c/p\u003e\u003cp\u003eIt is noteworthy that our analysis focuses on children (most studies targeted school-age populations). VKC primarily manifests in childhood and often abates by late adolescence\u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e Therefore, an 8.1% pooled prevalence effectively refers to the pediatric segment of the population. If one were to consider the total general population including adults, the prevalence would be lower (since VKC seldom persists beyond the teens or early twenties\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e In this sense, our figures highlight the pediatric burden specifically. This has public health implications: it underscores the importance of school health programs and pediatric ophthalmology services in Africa, as VKC can cause significant morbidity (e.g. chronic discomfort, corneal complications leading to visual impairment) at a young age.\u003c/p\u003e\u003cp\u003eEncouragingly, we found \u003cb\u003eno indication of publication bias\u003c/b\u003e in our review. Both visual inspection of the funnel plot and formal tests suggest that smaller studies were not systematically reporting higher or lower prevalences than larger studies. This adds confidence that our pooled result is not skewed by selective reporting. That said, we recognize that research on VKC prevalence in Africa might be subject to the \u0026ldquo;file drawer\u0026rdquo; problem in a different way: regions with \u003cem\u003eno data\u003c/em\u003e at all. There are many countries in Africa with no published VKC prevalence studies. Our eight-country coverage, while broad, leaves out large portions of the continent (for example, we found no prevalence surveys from any country in Southern Africa, and data from central African countries were very limited, with DRC represented by a single clinical series of VKC cases). This gap could mean that the true continental burden might differ if those unstudied areas have systematically lower or higher rates. We suspect that if VKC were a significant problem in Southern Africa, it might have been reported, and indeed some evidence suggests VKC is less common in far southern latitudes\u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e but absence of evidence is not evidence of absence. More epidemiological research is needed in those regions.\u003c/p\u003e\u003cp\u003eOur study has several \u003cb\u003estrengths\u003c/b\u003e. We adhered to a rigorous methodology for study selection, data extraction, and analysis, including duplicate independent review which minimizes bias. By using a random-effects model, we acknowledged and accounted for the high heterogeneity rather than treating these diverse studies as equivalent. The use of logit transformation is appropriate for prevalence data especially when some studies have moderately high prevalence percentages, as it prevents distortion of the confidence intervals. We also attempted to explore heterogeneity via meta-regression, which, while not yielding a definitive explanation, at least quantitatively confirmed that one country\u0026rsquo;s data (Mali) was an outlier. Furthermore, our inclusion of both published journal articles and accessible gray literature (e.g. theses or repository reports where available) reduces the likelihood that we missed major studies.\u003c/p\u003e\u003cp\u003eHowever, there are important \u003cb\u003elimitations\u003c/b\u003e to acknowledge. Foremost, the heterogeneity of ~\u0026thinsp;97% is extremely high, which means the pooled prevalence should be interpreted with caution. The 8.1% figure is an average of very disparate values; it does not imply that any given country or region in Africa will have ~\u0026thinsp;8% VKC prevalence. Instead, some places will be much lower and others much higher. Our subgroup analysis by country was limited by having only one or two studies per country (and none for many countries), which reduces statistical power. It is possible that with more data, clear regional patterns would emerge (for instance, perhaps West Africa on average has higher prevalence than North or East, as one might suspect from our dataset). Another limitation is that diagnostic criteria for VKC were not uniform by a single protocol \u0026ndash; although VKC\u0026rsquo;s clinical picture is characteristic, there is some subjectivity in determining what severity or signs qualify as VKC. Some studies might have included only moderate-to-severe VKC, while others counted mild cases with only seasonal itching and minimal signs. This could lead to differential misclassification. For example, if one study used a very stringent definition, it might undercount cases compared to a study using a broad definition. Unfortunately, details on diagnostic thresholds were not always thoroughly described in the articles. We mitigated this by ensuring each study claimed to be diagnosing VKC via clinicians, but subtle differences likely remain.\u003c/p\u003e\u003cp\u003eAdditionally, variations in \u003cb\u003estudy setting\u003c/b\u003e likely introduced bias. School surveys (which constituted a good portion of our data) generally capture both symptomatic and asymptomatic cases by directly examining children. Hospital-based studies, on the other hand, inherently look at those who came in with ocular complaints, which may overestimate prevalence if taken as representative of the general population. For instance, one Nigerian hospital-based study found a high prevalence among its attendees \u0026ndash; but that doesn\u0026rsquo;t translate to the community at large, it just shows VKC is a common diagnosis among pediatric ophthalmology patients. We excluded pure case series that didn\u0026rsquo;t define a population at risk (like a series of VKC patients only), but a few included studies were essentially surveys of those presenting to clinics for eye checks. We considered those as prevalence among clinic attendees, which is a biased sample of the general population. This kind of inclusion could skew the results upward. However, the majority of included studies were population-based (school or community), which lends greater credibility to the pooled estimate. We performed a sensitivity check excluding the obvious outlier study from Mali and any clearly clinic-based studies; the pooled prevalence in that scenario dropped slightly and heterogeneity decreased, but the prevalence still remained high (on the order of ~\u0026thinsp;5\u0026ndash;6%), reinforcing that VKC prevalence is elevated in Africa even under conservative assumptions.\u003c/p\u003e\u003cp\u003eFinally, we should note that our meta-analysis inherently gives more weight to studies with larger sample sizes (after logit transform). This means, for example, the large Ghana study (with 3,800 children) and the large Egyptian study (3,706 children) had a strong influence on the pooled estimate. Those studies had mid-range prevalence (~\u0026thinsp;9\u0026ndash;10% and ~\u0026thinsp;3\u0026ndash;4%, respectively), which may have tempered the influence of smaller studies that found very high prevalence. If larger-scale research were done in, say, Mali or Nigeria confirming the very high rates in those locales, the continental average could be revised upward. In other words, our result might be slightly conservative if some of the extreme prevalences came from studies with relatively smaller N (which carry less weight in the meta-analysis). That said, the largest study (Ghana) itself reported\u0026thinsp;~\u0026thinsp;9.4%, close to our mean, which adds some reassurance.\u003c/p\u003e\u003cp\u003eIn light of these findings, what are the implications? Firstly, \u003cb\u003eVKC should be recognized as a significant childhood eye health issue in Africa\u003c/b\u003e. Eye care services in endemic regions need to be equipped to diagnose and manage VKC. This includes training primary healthcare workers and optometrists to recognize VKC early and initiate treatment or referrals. Early management (with topical anti-allergic medications, mast-cell stabilizers, etc.) can prevent complications like corneal ulcers and permanent scarring. Secondly, there may be a need for \u003cb\u003epreventive strategies\u003c/b\u003e in high-prevalence communities. For example, health education could be provided to families about reducing exposure to known exacerbating factors (dust, wind, etc.), though completely avoiding the climate is impractical. Provision of protective eyewear (sunglasses) for children during dusty seasons or improving indoor environments (to reduce dust mite exposure) might be beneficial in theory, although such interventions need study. Thirdly, our results highlight the importance of \u003cb\u003eschool screening programs\u003c/b\u003e. Routine screening of school children for VKC (especially at the start of hot seasons) could be implemented in hyperendemic areas; this would allow prompt treatment and could reduce school absenteeism due to VKC symptoms\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e As Nche et al. (2023) summarized, instituting childhood screening in sub-Saharan Africa could mitigate the quality-of-life impact of VKC by catching cases early.\u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eFrom a research standpoint\u003c/b\u003e, further investigations are needed to pinpoint \u003cem\u003ewhy\u003c/em\u003e certain regions have such high prevalence. Studies examining the role of climate data, allergen profiles, or genetic predispositions in different African sub-populations would be valuable. For instance, are children in the Sahel zone more genetically prone to atopy, or is it simply the extreme environment driving VKC? Additionally, longitudinal studies could determine the natural history of VKC in African patients (e.g., average duration until resolution, proportion that develop severe complications). While VKC is often described as \u0026ldquo;self-limiting\u0026rdquo; (resolving after puberty), in a setting with year-round or severe perennial allergen exposure, it might last longer or cause more chronic changes than in temperate climates.\u003c/p\u003e\u003cp\u003eIt is also instructive to compare our findings to existing global reviews. A recent comprehensive review by Bruschi et al. (2023) examined VKC epidemiology and clinical characteristics worldwide\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003eThey reiterated that VKC is largely a disease of tropical and subtropical youth. Our analysis provides concrete evidence to support that claim in the African context, adding that within the tropics, there can be micro-variations. Notably, prior reviews have not provided a pooled prevalence for Africa, likely due to heterogeneity or a narrative focus. By quantifying an average (with large uncertainty) we underscore that \u003cb\u003eAfrica as a whole carries a heavy VKC burden\u003c/b\u003e, albeit unevenly distributed. This should galvanize ophthalmic public health officials in Africa to allocate resources for VKC \u0026ndash; for example, ensuring the availability of medications like cromolyn sodium, antihistamine drops, or topical steroids for severe cases in clinics. It may also justify exploring more advanced therapies (e.g. immunomodulators like cyclosporine eye drops) in settings where VKC is severe and causes corneal damage, as has been tried elsewhere\u003csup\u003e\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u003c/sup\u003e\u003c/p\u003e\u003cp\u003eIn conclusion, our systematic review and meta-analysis reveal that VKC is a common pediatric ocular allergy in Africa, affecting on the order of 8% of children on average and up to a third in the highest-prevalence regions. The condition\u0026rsquo;s prevalence varies widely by locale, reflecting environmental and possibly socio-demographic influences. \u003cb\u003eStandardized diagnostic criteria and improved epidemiological surveillance\u003c/b\u003e are needed to better map the risk factors and true prevalence of VKC across all parts of Africa. Eye health programs in Africa should integrate VKC awareness and management, as timely treatment can prevent the potentially blinding complications of this disease. Given that VKC can cause chronic discomfort and visual impairment during a child\u0026rsquo;s formative years, addressing this condition is important for improving children\u0026rsquo;s quality of life and educational performance. Our findings provide a baseline for health authorities and clinicians: in many African communities, a considerable fraction of children will have VKC \u0026ndash; these children need access to care. Future interventions might include school-based screening and treatment campaigns during high-incidence seasons, as well as community education on minimizing exposure to common allergens. Finally, further research should investigate targeted preventive measures and the potential benefit of immunotherapy in high-prevalence populations. By acknowledging and confronting the high prevalence of VKC in Africa, we can work towards reducing the burden of this disease and its impact on the vision and well-being of African children.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eVernal keratoconjunctivitis is a prevalent ocular condition among African children and adolescents, with an overall prevalence of around 8% and significant variation between regions. Certain areas (particularly in West Africa) experience an exceptionally high burden of VKC, whereas others have more moderate levels. The condition constitutes a notable cause of ocular morbidity in Africa, underlining the importance of dedicating attention and resources to its management. Standardized diagnostic and reporting methods would aid in better understanding the geographic distribution of VKC. Eye care services in Africa should be strengthened to provide early detection and appropriate treatment for VKC, in order to prevent complications such as corneal damage and to improve the quality of life of affected children. Public health initiatives, including school screenings and allergen exposure mitigation strategies, may be warranted in high-prevalence communities. In summary, VKC remains an important pediatric eye health challenge in Africa, and coordinated efforts in surveillance, research, and clinical care are needed to address this allergic eye disease and its consequences.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics and Declarations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthical approval and consent to participate:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe current research involved a review of available aggregate data, precluding the necessity of gathering new data related to human subjects. Therefore, informed consent and ethical approval were not necessary. All the data used in the current research were derived from research that had received their respective ethical clearance, as recorded in the source publications.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for Publication:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable (no individual person’s data).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of Data and Materials:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll data analyzed in this study were extracted from published articles included in the references. The extracted numerical data and analysis code are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting Interests:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no competing interests to declare.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. It was self-funded by the authors and their affiliated institution.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors’ Contributions:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDr.Mohamed Farah Ismail conceived and planned the study, conducted the literature search, executed data extraction, conducted statistical analysis, and prepared the manuscript. Prof. Intisar Khalafalla and Dr. Abdulkarim Ismail Qarbote critically reviewed the methodology, validated the data, and revised manuscripts And All authors read and approved the final manuscript\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments:\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors thank the Department of Ophthalmology at Kampala International University Teaching Hospital for their support and access to resources. We also acknowledge the contributions of colleagues who provided feedback on the study protocol and preliminary findings.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eThera JP. Magnitude of vernal kerato conjunctivitis among school children in Koulikoro. 2016; Available from: https://doi.org/10.36347%2Fsjams.2016.v04i01.032\u003c/li\u003e\n\u003cli\u003eSithole HL. Understanding vernal keratoconjunctivitis in children. Afr vis eye health [Internet]. 2020 Sep 21 [cited 2025 Jul 6];79(1). Available from: https://avehjournal.org/index.php/aveh/article/view/533\u003c/li\u003e\n\u003cli\u003eAli A, Bielory L, Dotchin S, Hamel P, Strube YNJ, Koo EB. Management of vernal keratoconjunctivitis: Navigating a changing treatment landscape. Survey of Ophthalmology [Internet]. 2024 Mar [cited 2025 Jul 6];69(2):265\u0026ndash;78. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0039625723001388\u003c/li\u003e\n\u003cli\u003eIbraheim KA, Ahmed HG. Vernal Keratoconjunctivitis in Sudan and Its Impact on Visual Acuity. EJHS [Internet]. 2024 May 17 [cited 2025 Jul 6];10(3):44\u0026ndash;63. Available from: https://ajpojournals.org/journals/index.php/EJHS/article/view/2025\u003c/li\u003e\n\u003cli\u003eAhmed SamahMM, Ahmed KEG, El Morsy O, Soliman S. Epidemiology of Vernal Keratoconjunctivitis (VKC) among children aged (12\u0026ndash;15) years - Menofia Governorate, Egypt. Delta J Ophthalmol [Internet]. 2019 [cited 2025 Jul 6];20(1):1. Available from: https://journals.lww.com/10.4103/DJO.DJO_42_18\u003c/li\u003e\n\u003cli\u003eMarey HM, Mandour SS, El Morsy OA, Farahat HG, Shokry SM. Impact of Vernal Keratoconjunctivitis on School Children in Egypt. Seminars in Ophthalmology [Internet]. 2017 Sep 3 [cited 2025 Jul 6];32(5):543\u0026ndash;9. Available from: https://www.tandfonline.com/doi/full/10.3109/08820538.2015.1123737\u003c/li\u003e\n\u003cli\u003eJaphet Pobanou. Magnitude of vernal kerato conjunctivitis among school children in Koulikoro. SJAMS [Internet]. 2016; Available from: https://doi.org/10.36347%2Fsjams.2016.v04i01.032\u003c/li\u003e\n\u003cli\u003eDuke RE, Odey F, De Smedt S. Vernal Keratoconjunctivitis in Public Primary School Children in Nigeria: Prevalence and Nomenclature. Epidemiology Research International [Internet]. 2016 Jul 18 [cited 2025 Jul 6];2016:1\u0026ndash;6. Available from: https://www.hindawi.com/journals/eri/2016/9854062/\u003c/li\u003e\n\u003cli\u003eOkoye O, Umeh R, Ezepue F. Prevalence of eye diseases among school children in a rural south-eastern Nigerian community. RRH [Internet]. 2013 Sep 29 [cited 2025 Jul 6]; Available from: https://www.rrh.org.au/journal/article/2357\u003c/li\u003e\n\u003cli\u003eAbah E, Oladigbolu K, Samaila E, Gani - Ikilama A. Ocular disorders in children in Zaria children\u0026prime;s school. Niger J Clin Pract [Internet]. 2011 [cited 2025 Jul 6];14(4):473. Available from: https://journals.lww.com/10.4103/1119-3077.91759\u003c/li\u003e\n\u003cli\u003eUkponmwan CU. Vernal Keratoconjunctivitis in Nigerians: 109 Consecutive Cases. Trop Doct [Internet]. 2003 Oct [cited 2025 Jul 6];33(4):242\u0026ndash;5. Available from: https://journals.sagepub.com/doi/10.1177/004947550303300419\u003c/li\u003e\n\u003cli\u003eAlemayehu AM, Yibekal BT, Fekadu SA. Prevalence of vernal keratoconjunctivitis and its associated factors among children in Gambella town, southwest Ethiopia, June 2018. Wolffsohn J, editor. PLoS ONE [Internet]. 2019 Apr 18 [cited 2025 Jul 6];14(4):e0215528. Available from: https://dx.plos.org/10.1371/journal.pone.0215528\u003c/li\u003e\n\u003cli\u003eHayilu D, Legesse K, Lakachew N, Asferaw M. Prevalence and associated factors of vernal keratoconjunctivitis among children in Gondar city, Northwest Ethiopia. BMC Ophthalmol [Internet]. 2016 Dec [cited 2025 Jul 6];16(1):167. Available from: http://bmcophthalmol.biomedcentral.com/articles/10.1186/s12886-016-0345-7\u003c/li\u003e\n\u003cli\u003eKassahun F, Bejiga A. Vernal keratoconjunctivitis among primary school students in Butajira Town. Ethiop J Health Dev. \u003c/li\u003e\n\u003cli\u003eSmedt SD, Nkurikiye J, Fonteyne Y, Hogewoning A, Esbroeck MV, Bacquer DD, et al. Vernal Keratoconjunctivitis in School Children in Rwanda and Its Association with Socio-Economic Status: A Population-Based Survey. The American Society of Tropical Medicine and Hygiene [Internet]. 2011 Oct 1 [cited 2025 Jul 6];85(4):711\u0026ndash;7. Available from: https://www.ajtmh.org/view/journals/tpmd/85/4/article-p711.xml\u003c/li\u003e\n\u003cli\u003eMuamba Nkashama L, Kayembe Lubeji D, Mwanza Kasongo JC, Kadima Mutombo T, Nyembue Tshipukane D. Sensitization and Clinical Characteristics of Congolese Children with Vernal Keratoconjunctivitis in Kinshasa. Ocular Immunology and Inflammation [Internet]. 2023 Jan 2 [cited 2025 Jul 6];31(1):15\u0026ndash;20. Available from: https://www.tandfonline.com/doi/full/10.1080/09273948.2021.1976217\u003c/li\u003e\n\u003cli\u003eAli A, Bielory L, Dotchin S, Hamel P, Strube YNJ, Koo EB. Management of vernal keratoconjunctivitis: Navigating a changing treatment landscape. Survey of Ophthalmology [Internet]. 2024 Mar [cited 2025 Jul 6];69(2):265\u0026ndash;78. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0039625723001388\u003c/li\u003e\n\u003cli\u003eNche EN, Okwen MM, Solomon A. Prevalence and clinical characteristics of vernal keratoconjunctivitis in sub-Saharan Africa. Current Opinion in Allergy \u0026amp; Clinical Immunology [Internet]. 2023 Oct [cited 2025 Jul 5];23(5):423\u0026ndash;9. Available from: https://journals.lww.com/10.1097/ACI.0000000000000928\u003c/li\u003e\n\u003cli\u003eIbraheim KA, Ahmed HG. Vernal Keratoconjunctivitis in Sudan and Its Impact on Visual Acuity. EJHS [Internet]. 2024 May 17 [cited 2025 Jul 6];10(3):44\u0026ndash;63. Available from: https://ajpojournals.org/journals/index.php/EJHS/article/view/2025\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7151855/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7151855/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground:\u003c/strong\u003e VKC is a chronic, allergic ocular surface disease that mostly affects children and adolescents in tropical regions. It can significantly impact vision and quality of life if not treated or if severe. VKC information on African populations is limited and region-specific, with some indications of very high prevalence in certain areas.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eObjective: T\u003c/strong\u003eo estimate the pooled prevalence of VKC in Africa and to investigate the heterogeneity between different regions of Africa\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis meta-analysis and systematic review presents the first pooled estimate of the prevalence of vernal keratoconjunctivitis (VKC) in African children.\u003cstrong\u003e\u003cbr\u003e\n Methods: \u003c/strong\u003eA systematic review and meta-analysis were undertaken according to the PRISMA 2020 guidelines. A comprehensive search on PubMed, Google Scholar, African Journals Online, and institutional repositories (2000-2025) was carried out to identify observational studies reporting the prevalence of VKC in African populations. Two reviewers independently screened and selected the studies, extracted data related to sample size, VKC cases, study setting, and diagnostic criteria, and evaluated the studies' quality using the JBI checklist for prevalence studies. A random-effects meta-analysis using logit transformation of proportions was performed to pool prevalence estimates. Heterogeneity assessment was performed using the Q-statistic, I², and τ², and meta-regression analysis by country was used to explore differences among studies. Potential publication bias was tested using funnel plot analysis and Egger’s test.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e Fourteen studies (N ≈ 20,000 individuals) from 7 African countries met the inclusion criteria. The overall prevalence of VKC was estimated as 8.1% (with a 95% confidence interval of about 6% to 12%). Prevalence was very variable across different settings, from about 3% among certain North African communities to as much as 37% within certain zones of West Africa. The level of heterogeneity was high (Q = 272.741, p \u0026lt; 0.001; τ² = 0.443), reflecting high variability across the studies in question. Country-specific meta-regression analysis was not statistically significant overall (p = 0.109); however, one particular country (Mali) had significantly higher prevalence than others (p = 0.010). There was also no significant asymmetry of the funnel plot (p \u0026gt; 0.4), suggesting that there was no significant publication bias.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion:\u003c/strong\u003e VKC affects a considerable proportion of the population in Africa, especially children, with marked regional variation. This high burden calls for increased awareness, early diagnosis, and region-appropriate preventive and management strategies to mitigate vision-threatening complications of VKC.\u003c/p\u003e","manuscriptTitle":"Epidemiology of Vernal Keratoconjuctivitis in African Children: A Systematic Review and Meta- Analysis","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-26 16:49:13","doi":"10.21203/rs.3.rs-7151855/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"799dc1e3-2b42-4327-964c-f28a3df8424e","owner":[],"postedDate":"November 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-03-13T11:11:26+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-26 16:49:13","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7151855","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7151855","identity":"rs-7151855","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}