Malaria vaccination coverage, completeness, and timeliness among children aged 6–24 months: a cross-sectional survey conducted in the Western region of Cameroon, 1 year following the vaccine introduction

Malaria vaccination coverage, completeness, and timeliness among children aged 6–24 months: a cross-sectional survey conducted in the Western region of Cameroon, 1 year following the vaccine introduction | medRxiv /* */ /* */ <!-- <!-- /*! * yepnope1.5.4 * (c) WTFPL, GPLv2 */ (function(a,b,c){function d(a){return"[object Function]"==o.call(a)}function e(a){return"string"==typeof a}function f(){}function g(a){return!a||"loaded"==a||"complete"==a||"uninitialized"==a}function h(){var a=p.shift();q=1,a?a.t?m(function(){("c"==a.t?B.injectCss:B.injectJs)(a.s,0,a.a,a.x,a.e,1)},0):(a(),h()):q=0}function i(a,c,d,e,f,i,j){function k(b){if(!o&&g(l.readyState)&&(u.r=o=1,!q&&h(),l.onload=l.onreadystatechange=null,b)){"img"!=a&&m(function(){t.removeChild(l)},50);for(var d in y[c])y[c].hasOwnProperty(d)&&y[c][d].onload()}}var j=j||B.errorTimeout,l=b.createElement(a),o=0,r=0,u={t:d,s:c,e:f,a:i,x:j};1===y[c]&&(r=1,y[c]=[]),"object"==a?l.data=c:(l.src=c,l.type=a),l.width=l.height="0",l.onerror=l.onload=l.onreadystatechange=function(){k.call(this,r)},p.splice(e,0,u),"img"!=a&&(r||2===y[c]?(t.insertBefore(l,s?null:n),m(k,j)):y[c].push(l))}function j(a,b,c,d,f){return q=0,b=b||"j",e(a)?i("c"==b?v:u,a,b,this.i++,c,d,f):(p.splice(this.i++,0,a),1==p.length&&h()),this}function k(){var a=B;return a.loader={load:j,i:0},a}var l=b.documentElement,m=a.setTimeout,n=b.getElementsByTagName("script")[0],o={}.toString,p=[],q=0,r="MozAppearance"in l.style,s=r&&!!b.createRange().compareNode,t=s?l:n.parentNode,l=a.opera&&"[object Opera]"==o.call(a.opera),l=!!b.attachEvent&&!l,u=r?"object":l?"script":"img",v=l?"script":u,w=Array.isArray||function(a){return"[object Array]"==o.call(a)},x=[],y={},z={timeout:function(a,b){return b.length&&(a.timeout=b[0]),a}},A,B;B=function(a){function b(a){var a=a.split("!"),b=x.length,c=a.pop(),d=a.length,c={url:c,origUrl:c,prefixes:a},e,f,g;for(f=0;f<d;f++)g=a[f].split("="),(e=z[g.shift()])&&(c=e(c,g));for(f=0;f<b;f++)c=x[f](c);return c}function g(a,e,f,g,h){var i=b(a),j=i.autoCallback;i.url.split(".").pop().split("?").shift(),i.bypass||(e&&(e=d(e)?e:e[a]||e[g]||e[a.split("/").pop().split("?")[0]]),i.instead?i.instead(a,e,f,g,h):(y[i.url]?i.noexec=!0:y[i.url]=1,f.load(i.url,i.forceCSS||!i.forceJS&&"css"==i.url.split(".").pop().split("?").shift()?"c":c,i.noexec,i.attrs,i.timeout),(d(e)||d(j))&&f.load(function(){k(),e&&e(i.origUrl,h,g),j&&j(i.origUrl,h,g),y[i.url]=2})))}function h(a,b){function c(a,c){if(a){if(e(a))c||(j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}),g(a,j,b,0,h);else if(Object(a)===a)for(n in m=function(){var b=0,c;for(c in a)a.hasOwnProperty(c)&&b++;return b}(),a)a.hasOwnProperty(n)&&(!c&&!--m&&(d(j)?j=function(){var a=[].slice.call(arguments);k.apply(this,a),l()}:j[n]=function(a){return function(){var b=[].slice.call(arguments);a&&a.apply(this,b),l()}}(k[n])),g(a[n],j,b,n,h))}else!c&&l()}var h=!!a.test,i=a.load||a.both,j=a.callback||f,k=j,l=a.complete||f,m,n;c(h?a.yep:a.nope,!!i),i&&c(i)}var i,j,l=this.yepnope.loader;if(e(a))g(a,0,l,0);else if(w(a))for(i=0;i (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];var j=d.createElement(s);var dl=l!='dataLayer'?'&l='+l:'';j.src='//www.googletagmanager.com/gtm.js?id='+i+dl;j.type='text/javascript';j.async=true;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-P4HH5NV'); Skip to main content Home About Submit ALERTS / RSS Search for this keyword Advanced Search Malaria vaccination coverage, completeness, and timeliness among children aged 6–24 months: a cross-sectional survey conducted in the Western region of Cameroon, 1 year following the vaccine introduction Jerome Ateudjieu , View ORCID Profile Merveille Claire Nana Djapou , Benjamin Kevin Bekoa Onana , View ORCID Profile Abdias Aron Tatsabong Tiomeni , View ORCID Profile Gretta Ludivine Okoumokath Mpande , Donald Kapso Nanguep , View ORCID Profile Collins Buh Nkum , View ORCID Profile Dora Winny Ateudjieu Kenfack , Anne Cecile Bissek doi: https://doi.org/10.1101/2025.09.24.25336598 Jerome Ateudjieu 1 Department of Public Health, Faculty of Medecine and Pharmaceutical Sciences, University of Dschang , Cameroon 2 Meilleur Accès aux Soins de Santé , Yaoundé, Cameroon 3 Division of Health Operations Research, Cameroon Ministry of Public health Find this author on Google Scholar Find this author on PubMed Search for this author on this site Merveille Claire Nana Djapou 2 Meilleur Accès aux Soins de Santé , Yaoundé, Cameroon Find this author on Google Scholar Find this author on PubMed Search for this author on this site ORCID record for Merveille Claire Nana Djapou For correspondence: Merveille_claire{at}yahoo.com Benjamin Kevin Bekoa Onana 2 Meilleur Accès aux Soins de Santé , Yaoundé, Cameroon Find this author on Google Scholar Find this author on PubMed Search for this author on this site Abdias Aron Tatsabong Tiomeni 2 Meilleur Accès aux Soins de Santé , Yaoundé, Cameroon Find this author on Google Scholar Find this author on PubMed Search for this author on this site ORCID record for Abdias Aron Tatsabong Tiomeni Gretta Ludivine Okoumokath Mpande 2 Meilleur Accès aux Soins de Santé , Yaoundé, Cameroon Find this author on Google Scholar Find this author on PubMed Search for this author on this site ORCID record for Gretta Ludivine Okoumokath Mpande Donald Kapso Nanguep 2 Meilleur Accès aux Soins de Santé , Yaoundé, Cameroon Find this author on Google Scholar Find this author on PubMed Search for this author on this site Collins Buh Nkum 2 Meilleur Accès aux Soins de Santé , Yaoundé, Cameroon Find this author on Google Scholar Find this author on PubMed Search for this author on this site ORCID record for Collins Buh Nkum Dora Winny Ateudjieu Kenfack 4 Department of Microbiology, faculty of Sciences, University of Yaounde 1 , Cameroon 5 Centre for Research on Emerging and Re-emerging Diseases CREMER , Cameroon Find this author on Google Scholar Find this author on PubMed Search for this author on this site ORCID record for Dora Winny Ateudjieu Kenfack Anne Cecile Bissek 3 Division of Health Operations Research, Cameroon Ministry of Public health Find this author on Google Scholar Find this author on PubMed Search for this author on this site Abstract Full Text Info/History Metrics Data/Code Preview PDF Abstract Malaria vaccination was introduced as part of Cameroon EPI vaccine to prevent malaria morbidity and mortality among children aged 6-24 months. This study aims to assess the coverage, completeness, and timeliness of this vaccine, and explore parental perceptions on children access to vaccination. This was a community-based, descriptive cross-sectional study targeting children aged from 6 to 24months and caregivers, selected by stratified cluster random sampling in Foumbot and Foumban health districts. Data were collected from caregivers by trained and supervised enumerators using a face-to-face, pretested questionnaire. Malaria vaccine coverage, completeness, and timeliness were estimated with 95% confidence interval. The contribution of caregivers’ perception on the first dose malaria vaccination status was explored by estimating crude Odd Ratio (cOR) and Adjusted Odd ratio (aOR) estimated from mixed effect logistic regression. Of the 55 targeted and reached clusters 399 children were included in this study. Vaccination coverage of the first, second and the third dose malaria vaccination was 31.20% (95%CI 30.38 - 32.02), 22.61% (95%CI 21.85 - 23.37) and 17.70% (95%CI 16.88 - 18.52) respectively. Among the children exposed to the first dose, 56.49% (95%CI 44.61 - 68.37) completed the third dose. The timeliness of the three administered doses was around 50-57%. In multivariate analysis, parental perception remained significantly associated with dose 1 malaria administration (aOR 15.54 95%CI 12.63 - 19.10 p= <0.001), dose 1 timeliness (aOR 2.36 95%CI 1.52 - 3.65 p= <0.001) and dose 2 completeness (aOR 9.81 95%CI 7.78 - 12.36 p= <0.001). More than a year after the malaria vaccine introduction in the health districts of Foumbot and Foumban, the performance indicators for this vaccination are below expectations for the vaccine to have a significant impact on reducing malaria morbidity in children. Communicating to positively influence caregivers’ perceptions on malaria vaccination expected to contribute in improving the situation. Background Malaria remains a public health challenge worldwide with the highest burden in Africa [ 1 , 2 ]. Many interventions have been prioritized to reduce the disease burden including environmental interventions, the use of long-lasting mosquito nets, prophylactic treatment regarding vulnerable groups including pregnant women and children in malaria epidemic areas [ 3 - 6 ]. The impact of these interventions have been notable with significant reduction of disease morbidity and mortality but more needs to be done to control the disease [ 7 ]. In line with this, vaccine development has delivered the marketing of RTS,S/AS01, R21/Matrix-M and PfSPZ, with RTS,S/AS01 and R21/Matrix-M recommended by WHO [ 8 - 15 ]. Available literature documents the efficacy, safety and benefits of malaria vaccination in a variety of contexts [ 7 , 11 , 16 ]. These data, consolidated after the pilot projects carried out as part of the Expanded Immunization Programs in Kenya, Ghana and Malawi, and the WHO recommendations that followed, have helped to justify the extension of interventions to other countries, including Cameroon [ 15 - 18 ]. This was followed by important reported challenges that included logistic difficulties, funding constraints, the complexity of administering of the four-dose vaccine, and poor caregivers’ adherence in some contexts [ 19 , 20 ]. In Cameroon RTS,S/AS01 was introduced in 2024 as a part of expanded national immunization program targeting children aged 6-24 months of 42 health districts with highest malaria burden in children. By the ten month from the beginning of the introduction, administrative data reported 44.8% third dose coverage [ 21 ]. Exploring this coverage and caregivers’ perceptions of malaria vaccination in households should generate evidence for planning interventions to reach the maximum number of targeted children. Methodology 1. Study design This was a community-based descriptive cross-sectional study targeting children aged 6 to 24 months, selected by stratified cluster random sampling. Data were collected using a face-to-face questionnaire administered to caregivers and a grid to review children vaccination booklet. Malaria vaccine coverage, completeness and timeliness were estimated from the collected data. 2. Study setting The study was conducted in the Foumban and Foumbot health district in the West Region of Cameroon ( Figure 1 ) which were the only two districts in the region benefiting from the malaria EPI vaccination program at the time of the study. Download figure Open in new tab Figure 1: Foumban and Foumbot Districts Map 3. Study population Children aged 6 to 24 months living in the Foumbot or Foumban health district were eligible. Those with caregivers consenting to participate were included. Children with no caregiver to provide data on vaccination status and those living in health areas with recent history of insecurity were excluded. 4. Sample size estimation The minimum sample size estimated was 392 couple mother-child. This estimation assumed a third dose malaria coverage of 50%, a 95% confidence level, a precision of 7% and a cluster design effect of 2. Assuming to reach about 7 children per cluster, the estimated sample was allocated across 55 clusters. 5. Sampling process Stratified by the population size of Foumban and Foumbot health districts, six and three health areas, respectively, were randomly selected to be part of the study. Each health area, the list of communities and their respective population size was obtained. Clusters were then allocated proportionally to communities’ population size using a stratified systematic sampling approach. In targeted community participants of each cluster were selected by randomly selecting and a direction of recruitment. Households bordering the street were visited following the direction to identify and enrol study participants. Recruitment was considered completed in each cluster when about 7 children were included. 6. Data collection tools and variable Data were collected using a face-to-face administered questionnaire and a grid to review vaccination cards. These tools were adapted from an existing questionnaire that was originally developed to assess documented and undocumented EPI vaccination coverage, timeliness and completeness [ 22 , 23 ]. The main data collected included the sociodemographic characteristics of the mother and children; child’s malaria vaccination status; caregiver’s exposure to malaria vaccination information, as well as their perception of the malaria vaccination benefits and safety. 7. Data collection process The process involved obtaining informed consent from caregivers, administering the questionnaire and collecting data vaccination data from the vaccination card when accessible. 8. Data analysis We estimated the documented vaccine coverage, timeliness, completeness using numerators and denominators as presented in table 1 . Weighting was applied for these estimates considering stratified distribution of allocated clusters per health area. We explored the contribution of caregivers’ perception regarding malaria vaccine on first malaria documented dose coverage and second dose malaria vaccine completeness using case control approach estimating and adjusting Odds Ratio. Adjustment was done using mixed effect logistic regression with confounders identified from the comparison of key characteristics between cases and controls. Controls being children documented vaccinated and cases being children with no documented vaccination. Data were analyzed using SPSS version 24.0 and Excel 2013. Estimates were reported with 95% confidence intervals. View this table: View inline View popup Download powerpoint Table 1: Definition of denominators and numerators for the estimate of the documented vaccine coverage, timeliness, completeness of the malaria vaccines uptake. 9. Ethical consideration The present study was conducted to generate evidence for the improvement of malaria vaccination in Cameroon. Its implementation involved household-based data collection from caregiver with risk of increasing access to participants confidential data and compromising their autonomy. Participants were informed of the aims and procedures of the study and were included only when they consented to participate by signing the consent form. Participants’ confidentiality was protected by not collecting identifiable data, password protecting access to collected data and limiting access to dataset to the team in charge of data management and analyses. The protocol was evaluated by the competent ethical review committee (West Region Ethics Review Committee of Human Health Research of Cameroon) and approved with reference number N°/580/29/05/2024/CE/CERSH-OU. Results 1. Survey coverage We reached the 55 targeted clusters, and 399 participants all of whom consented to participate with average cluster coverage of 93.41% [95%CI: (91.32 – 95.50)]. 2. Socio-demographic characteristics of Caregiver and children The mean age of the caregiver and children were 27.38 ± 7.45 years and 14.24 ± 5.41 months respectively. Socio-demographic characteristics of the study population are presented in table 2 . The majority of caregivers (97.1%) were female; 11.5% were adolescents, and 37.5% had a low level of education. Table 3 presents the sociodemographic characteristics of the children. View this table: View inline View popup Table 2: Socio-demographic characteristics of caregiver View this table: View inline View popup Download powerpoint Table 3: Socio-demographic characteristics of children 3. Vaccine coverage, completeness and timeliness Of the 399 children reached, 208(51.9%) were reported by caregiver to have receive at least 01 dose of malaria vaccination; while 121(29.8%) were documented to have received at least 01 dose of malaria vaccination. Children vaccination coverage, timeliness and completeness are presented in table 4 . Of the included children, 48 (17.70%) were documented vaccinated with the third dose of malaria vaccine. Forty-six children (37.98%) of the 119 children exposed to the first dose completed the third dose. The timeliness of the three doses varied between 50.34% and 56.66%. View this table: View inline View popup Download powerpoint Table 4: Malaria vaccine coverage, completeness and timeliness 4. Caregivers’ perception on malaria vaccine Caregivers’ perceptions of the malaria vaccine are presented in Table 5 . Of the 399 included caregivers, 325 (81.8%) had positive perceptions of vaccination. View this table: View inline View popup Download powerpoint Table 5: Caregiver perceptions on malaria vaccination 5. Comparison of the distribution of socio-demographic characteristics between vaccinated and unvaccinated children Table 6 presents the distribution of sociodemographic characteristics between selected vaccination status. There was significant difference for sociodemographic characteristics between children with dose one malaria vaccination administration and those not benefiting dose one malaria vaccine administration. No significant differences were observed for caregiver age ≤19 years, occupation (farmer), religion (Muslim), or occupation (housekeeper) when comparing children who received the first dose on time versus those who did not, or for second-dose completeness. View this table: View inline View popup Table 6: Sociodemographic characteristics distribution between selected vaccination status of children 6. Association between caregivers’ perception and vaccination status of children Table 7 presents the contribution of malaria vaccine perception on selected children vaccination status. Children exposure to caregivers with positive perception of malaria vaccination increased their chance to benefit the first dose malaria vaccination, to be administered this dose in time and to complete two doses malaria vaccination. View this table: View inline View popup Download powerpoint Table 7: Bivariate association between vaccine perception and vaccination status of children Discussion To the best of our knowledge, this is the first community-based survey exploring the coverage, completeness, and timeliness of malaria vaccination since its introduction in Cameroon. Results suggest that, documented vaccine coverage was 31.20% for dose 1, 22.61% for dose 2, and 17.70% for dose 3. The completeness of the second and third doses was 74.76% and 56.49%, respectively, and the timeliness of the first, second, and third doses was 55.24%, 50.35%, and 56.66%, respectively. Children exposure to caregivers with positive perception of malaria vaccination increased their chance to benefit the first dose malaria vaccination, to be administered this dose in time and to complete two doses malaria vaccination. Vaccination coverage reflects the proportion of the target population that has benefited from the intervention. It is also an indicator of vaccine demand and of effectiveness of strategies implemented to reach targeted vaccination population. This study revealed that, less than one third of eligible children were documented to have benefited the first dose malaria vaccination. The second and third dose coverage of the malaria vaccination dropped to less than one fourth and to less than one fifth respectively. A study analysing administrative data reported a month following malaria vaccination introduction in Cameroon by the national EPI from the 42 targeted health districts revealed a first-dose malaria vaccine coverage relatively higher (37% of eligible children) than that of our study [ 24 ]. Fourteen months following the malaria vaccine introduction in Cameroon and one month prior to the data collected from this study, the three-dose malaria vaccination cumulative coverage from January to April 2025 reported by the national Expanded Program on Immunization was 64.3%, 54.1%, and 62.3% at national level, 53.9%, 40.6%, 42.2% in the two health districts targeted by our study for the first, second and third malaria vaccination dose respectively [ 25 ]. The discrepancies between these administrative data and this study is yet to be understood and can be explained by the children reached during vaccination session are not rigorously selected from communities belonging to vaccinating health district, by the fact that our study estimated only documented vaccination, and by probable error when estimating the numerator or denominator of administrative malaria vaccination coverage. The relatively higher malaria vaccination coverage estimated after the vaccine introduction in other countries can be explained by better communication prior to the vaccination introduction, resulting in better adherence of the caregivers and/or by vaccination strategies [ 16 , 26 ]. The coverage estimated from our study was below expectation of the national Cameroon EPI [ 27 ]. Assuming that the malaria vaccine introduced in Cameroon (RTS,S/AS01) retains its efficacy as reported in clinical trials, the three-dose vaccination coverage reported in our study predicts that nearly one in twenty children reaching their first birthday will benefit from the vaccine’s protection against malaria in the two targeted districts. This underlines the urgent need, on the one hand, to investigate the determinants of poor performance of malaria vaccination and, on the other hand, to implement documented interventions in the same context that has been shown to contribute to improving EPI vaccination coverage [ 23 ]. The vaccination completeness indicator is important for monitoring the performance of immunization programs [ 28 ]. It also provides information on the health system’s ability to ensure optimal protection for vaccinated children, as vaccine effectiveness depends on full compliance with the recommended vaccination schedule for each given vaccine. Malaria vaccination completeness is necessary to maximize individual immunity but also to significantly reduce malaria morbidity and mortality in children [ 11 ]. In this study, half of the children who started the malaria vaccine continued through to the third dose. The observed high dropout rate in our study appears to be consistent with varying levels of importance for malaria vaccine and other EPI vaccines as documented from studies conducted in similar and other contexts [ 29 ]. The present study was not planned to understand factors catalysing malaria vaccination dropout rate. In the absence of access to studies exploring vaccine completeness for malaria vaccination, the consultation of studies exploring it for other vaccines identified negative maternal perceptions of vaccination, the birth of the child in the community and limited geographical accessibility to vaccination appear to increase the risk of vaccine incompleteness [ 30 ]. Further studies should explore the contribution of these factors on malaria vaccination completeness and others such as the scheduling of vaccination sessions and the occurrence of adverse events after vaccination identified to induce vaccination hesitancy [ 31 ]. The benefit of other caregivers reminders using SMS or, tracking of children vaccination status in households by community volunteers to catch up on missed doses, shown to be beneficial for other vaccines, should be explored for their contribution to improving malaria vaccination completeness [ 23 , 31 ]. The timing and recommended interval between vaccine doses are based on the immune response and child development, as assessed through clinical trials and age-specific disease risks [ 32 , 33 ]. To our knowledge, no studies have yet been conducted to assess the timeliness of malaria vaccination in Cameroon. Like all EPI vaccines, malaria vaccination has an administration schedule, but this schedule does not provide an operational definition of vaccination timeliness. Considering in our study an administration of each dose of malaria vaccine within one month following the exact age of administration recommended in the EPI vaccination schedule, it turned out that approximately half of the children received their dose of vaccine on time. Comparing this trend with the timeliness of other EPI vaccines administered in the same context a few years earlier shows a higher timeliness rate for the BCG vaccine, which is administered at birth, and a timeliness rate consistent with our study for the DPT-Hi + Hb 3 vaccine, i.e., nearly half of children receiving the third dose of this vaccine within one month of the age recommended by the EPI [ 29 ]. This consistency probably matches the fact that nearly half of vaccinated children are vaccinated later than recommended is related to the supply or demand of all EPI vaccines and not just the malaria vaccine and has to be addressed by the program. Follow-up studies of children in high-risk areas show an increase in malaria incidence with increasing time following the administration each malaria vaccine dose, suggesting that some of the benefit of malaria vaccine is lost when the vaccine administration schedule is not respected [ 11 ]. Making available an operational definition of the timeliness of each vaccine dose, conducting studies to understand low vaccine timeliness, and identifying interventions to improve it should guide the Expanded Program on Immunization to improve malaria vaccine timeliness. Caregivers’ perception of children vaccination is expected to influence it demand in the benefit of children. In this study, a positive perception of the malaria vaccine was documented to significantly increase children access to the first malaria dose as well as the timeliness of the dose and the completeness of the second dose. To the best of our knowledge no published study has investigated the contribution of caregiver perception on malaria vaccine and children access to this vaccine. In Malawi, revealed evidence in line with our finding by documenting the contribution of caregivers’ exposure to negative rumors on the malaria vaccine and significant reduction of children likelihood of full uptake of the malaria vaccine [ 34 ]. This finding goes beyond the scope of the malaria vaccine. Indeed, a systematic review of general childhood vaccination revealed that negative perceptions of vaccines were significantly associated with non-use of vaccination [ 35 ]. Therefore, generating evidence on innovative interventions to improve caregivers’ perception on malaria vaccine is expected to guide decision makers in taking needed action to improve malaria vaccine uptake in children. The results of this study should be used taking in consideration following limitation. Malaria vaccination coverage, timeliness and completeness were estimated based on vaccination status. This could underestimate access to vaccination, as a given proportion of vaccinated children may be vaccinated without documentation [ 36 ]. Conclusion In conclusion, the coverage, completeness, and timeliness of malaria vaccination are below the targets needed to achieve optimal vaccination benefits. Children exposure to caregivers with positive perception of malaria vaccination increased their chance to benefit the first dose malaria vaccination, to be administered this dose in time and to complete two doses malaria vaccination. We recommend that the competent health authorities in the targeted health districts to implement communication initiatives aimed at improving caregivers’ perceptions on malaria vaccination; that scientists test innovative interventions to improve caregivers’ perceptions on malaria vaccination and that other determinants of children’s access to malaria vaccination be explored to guide decision-making on promoting children’s access to the malaria vaccine. Data Availability The database is available and accessible from the corresponding author. Acknowledgments We thank the health authorities of the Rest Region of Cameroon for facilitating and accomodating the implementation of the project. We also thank all enumerators and supervisors for their contribution in the data collection. References 1. ↵ WHO . Malaria 2024 [Available from: https://www.who.int/news-room/fact-sheets/detail/malaria . 2. ↵ wHO . Mobilizing communities to help prevent and control malaria in Cameroon 2022 [Available from: https://www.who.int/news-room/feature-stories/detail/mobilizing-communities-to-help-prevent-and-control-malaria-in-cameroon . 3. ↵ Li J , Docile HJ , Fisher D , Pronyuk K , Zhao L. Current Status of Malaria Control and Elimination in Africa: Epidemiology, Diagnosis, Treatment, Progress and Challenges . J Epidemiol Glob Health . 2024 ; 14 ( 3 ): 561 – 79 . OpenUrl PubMed 4. Xu M , Hu YX , Lu SN , Idris MA , Zhou SD , Yang J , et al. Seasonal malaria chemoprevention in Africa and China’s upgraded role as a contributor: a scoping review . Infect Dis Poverty . 2023 ; 12 ( 1 ): 63 . OpenUrl PubMed 5. González-Sanz M , Berzosa P , Norman FF . Updates on Malaria Epidemiology and Prevention Strategies . Curr Infect Dis Rep . 2023 : 1 – 9 . 6. ↵ WHO . GLOBAL TECHNICAL STRATEGY FOR MALARIA 2016–2030 2015 [Available from:file:///C:/Users/HP/Downloads/Documents/global-technical-strategy-for-malaria-2016-2030.pdf. 7. ↵ Nadeem AY , Shehzad A , Islam SU , Al-Suhaimi EA , Lee YS . Mosquirix™ RTS, S/AS01 Vaccine Development, Immunogenicity, and Efficacy . Vaccines (Basel) . 2022 ; 10 ( 5 ). 8. ↵ Zavala F. RTS,S: the first malaria vaccine . J Clin Invest . 2022 ; 132 ( 1 ). 9. Stanisic DI , Good MF . Malaria Vaccines: Progress to Date . BioDrugs . 2023 ; 37 ( 6 ): 737 – 56 . OpenUrl CrossRef PubMed 10. Duffy PE . Current approaches to malaria vaccines . Curr Opin Microbiol . 2022 ; 70 : 102227 . OpenUrl PubMed 11. ↵ Datoo MS , Dicko A , Tinto H , Ouédraogo JB , Hamaluba M , Olotu A , et al. Safety and efficacy of malaria vaccine candidate R21/Matrix-M in African children: a multicentre, double-blind, randomised, phase 3 trial . Lancet . 2024 ; 403 ( 10426 ): 533 – 44 . OpenUrl CrossRef PubMed 12. Duffy PE , Gorres JP , Healy SA , Fried M. Malaria vaccines: a new era of prevention and control . Nat Rev Microbiol . 2024 ; 22 ( 12 ): 756 – 72 . OpenUrl CrossRef PubMed 13. SANARIA . Sanaria’s PfSPZ Vaccine Achieves Durable Protection Against Heterologous Malaria Infection in a Clinical Trial 2017 [Available from: https://sanaria.com/2017/02/20/sanarias-pfspz-vaccine-achieves-durable-protection-against-heterologous-malaria-infection-in-a-clinical-trial/?utm_source=chatgpt.com . 14. Mwakingwe-Omari A , Healy SA , Lane J , Cook DM , Kalhori S , Wyatt C , et al. Two chemoattenuated PfSPZ malaria vaccines induce sterile hepatic immunity . Nature . 2021 ; 595 ( 7866 ): 289 – 94 . OpenUrl CrossRef PubMed 15. ↵ WHO . Malaria vaccines (RTS,S and R21) 2025 [Available from: https://www.who.int/news-room/questions-and-answers/item/q-a-on-rts-s-malaria-vaccine . 16. ↵ Asante KP , Mathanga DP , Milligan P , Akech S , Oduro A , Mwapasa V , et al. Feasibility, safety, and impact of the RTS,S/AS01(E) malaria vaccine when implemented through national immunisation programmes: evaluation of cluster-randomised introduction of the vaccine in Ghana, Kenya, and Malawi . Lancet . 2024 ; 403 ( 10437 ): 1660 – 70 . OpenUrl CrossRef PubMed 17. Asante KP , Binka FN , Koram KA . Malaria vaccine deployment in Africa: focus on Ghana . Ghana Med J . 2019 ; 53 ( 2 ): 90 – 1 . OpenUrl CrossRef PubMed 18. ↵ WHO . Cameroon kicks off malaria vaccine rollout 2024 [Available from: https://www.afro.who.int/countries/cameroon/news/cameroon-kicks-malaria-vaccine-rollout . 19. ↵ Adeshina OO , Nyame S , Milner J , Milojevic A , Asante KP . Barriers and facilitators to nationwide implementation of the malaria vaccine in Ghana . Health Policy Plan . 2023 ; 38 ( 1 ): 28 – 37 . OpenUrl PubMed 20. ↵ Hoyt J , Okello G , Bange T , Kariuki S , Jalloh MF , Webster J , et al. RTS,S/AS01 malaria vaccine pilot implementation in western Kenya: a qualitative longitudinal study to understand immunisation barriers and optimise uptake . BMC Public Health . 2023 ; 23 ( 1 ): 2283 . OpenUrl CrossRef PubMed 21. ↵ Cameroun P. RAPPORT MENSUEL DE SUIVI DU PLAN DE TRAVAIL ANNUEL 2024 . 22. ↵ Ateudjieu J , Yakum MN , Goura AP , Tembei Ayok M , Guenou E , Kangmo Sielinou CB , et al. An innovative approach in monitoring oral cholera vaccination campaign: integration of a between-round survey . BMC Public Health . 2022 ; 22 ( 1 ): 238 . OpenUrl PubMed 23. ↵ Ateudjieu J , Yakum NM , Goura AP , Guenou E , Beyala LB , Amada L , et al. Tracking Demographic Movements and Immunization Status to Improve Children’s Access to Immunization (TDM-IAI): Protocol for a Field-Based Randomized Controlled Trial . JMIR Res Protoc . 2021 ; 10 ( 2 ): e21734 . OpenUrl 24. ↵ Ndoula ST , Mboussou F , Njoh AA , Nembot R , Baonga SF , Njinkeu A , et al. Malaria Vaccine Introduction in Cameroon: Early Results 30 Days into Rollout . Vaccines (Basel) . 2024 ; 12 ( 4 ). 25. ↵ Cameroon P. RAPPORT MENSUEL DE SUIVI DU PLAN DE TRAVAIL ANNUEL Novembre 2024| Semaine 48 . 2024 . 26. ↵ Gavi . A turning point: Cameroon rolls out world’s first malaria vaccine 2024 [Available from: https://www.gavi.org/vaccineswork/turning-point-cameroon-rolls-out-worlds-first-malaria-vaccine . 27. ↵ PEV . PLAN DE TRAVAIL ANNUEL 2024 PROGRAMME ELARGI DE VACCINATION Cameroun . 2024 . 28. ↵ Organization GWH . A guide for conducting an Expanded Programme on Immunization (EPI) Review . 2017 . 29. ↵ Ateudjieu J , Yakum MN , Goura AP , Tembei AM , Ingrid DK , Bita’a Landry B , et al. EPI immunization coverage, timeliness and dropout rate among children in a West Cameroon health district: a cross sectional study . BMC Public Health . 2020 ; 20 ( 1 ): 228 . OpenUrl CrossRef PubMed 30. ↵ Bekuma TT , Seme A , Ahmed S , Abera M. Level and determinants of pentavalent vaccine dropout during infancy: A hierarchical analysis of community-level longitudinal study . PLoS One . 2025 ; 20 ( 6 ): e0326684 . OpenUrl PubMed 31. ↵ Malande OO , Munube D , Afaayo RN , Chemweno C , Nzoka M , Kipsang J , et al. Adverse events following immunization reporting and impact on immunization services in informal settlements in Nairobi, Kenya: a prospective mixed-methods study . Pan Afr Med J . 2021 ; 40 : 81 . OpenUrl PubMed 32. ↵ Saso A , Kampmann B. Vaccine responses in newborns . Semin Immunopathol . 2017 ; 39 ( 6 ): 627 – 42 . OpenUrl CrossRef PubMed 33. ↵ CDC . Timing and Spacing of Immunobiologics 2024 [Available from: https://www.cdc.gov/vaccines/hcp/imz-best-practices/timing-spacing-immunobiologics.html . 34. ↵ Simbeye AJ , Kumwenda S , Cohee LM , Omondi D , Masibo PK , Wao H , et al. Factors associated with malaria vaccine uptake in Nsanje district, Malawi . Malar J . 2024 ; 23 ( 1 ): 105 . OpenUrl PubMed 35. ↵ Smith LE , Amlôt R , Weinman J , Yiend J , Rubin GJ . A systematic review of factors affecting vaccine uptake in young children . Vaccine . 2017 ; 35 ( 45 ): 6059 – 69 . OpenUrl PubMed 36. ↵ Ateudjieu J , Tchio-Nighie KH , Yakum MN , Goura AP , Amada L , Sonkoua I , et al. Innovative approach in assessing the children’s immunization status when it cannot be documented . J Public Health Afr . 2023 ; 14 ( 9 ): 2450 . OpenUrl PubMed View the discussion thread. Back to top Previous Next Posted September 27, 2025. Download PDF Data/Code Email Thank you for your interest in spreading the word about medRxiv. NOTE: Your email address is requested solely to identify you as the sender of this article. Your Email * Your Name * Send To * Enter multiple addresses on separate lines or separate them with commas. 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Share Malaria vaccination coverage, completeness, and timeliness among children aged 6–24 months: a cross-sectional survey conducted in the Western region of Cameroon, 1 year following the vaccine introduction Jerome Ateudjieu , Merveille Claire Nana Djapou , Benjamin Kevin Bekoa Onana , Abdias Aron Tatsabong Tiomeni , Gretta Ludivine Okoumokath Mpande , Donald Kapso Nanguep , Collins Buh Nkum , Dora Winny Ateudjieu Kenfack , Anne Cecile Bissek medRxiv 2025.09.24.25336598; doi: https://doi.org/10.1101/2025.09.24.25336598 Share This Article: Copy Citation Tools Malaria vaccination coverage, completeness, and timeliness among children aged 6–24 months: a cross-sectional survey conducted in the Western region of Cameroon, 1 year following the vaccine introduction Jerome Ateudjieu , Merveille Claire Nana Djapou , Benjamin Kevin Bekoa Onana , Abdias Aron Tatsabong Tiomeni , Gretta Ludivine Okoumokath Mpande , Donald Kapso Nanguep , Collins Buh Nkum , Dora Winny Ateudjieu Kenfack , Anne Cecile Bissek medRxiv 2025.09.24.25336598; doi: https://doi.org/10.1101/2025.09.24.25336598 Citation Manager Formats BibTeX Bookends EasyBib EndNote (tagged) EndNote 8 (xml) Medlars Mendeley Papers RefWorks Tagged Ref Manager RIS Zotero Tweet Widget Facebook Like Google Plus One Subject Area Public and Global Health Subject Areas All Articles Addiction Medicine (567) Allergy and Immunology (863) Anesthesia (297) Cardiovascular Medicine (4412) Dentistry and Oral Medicine (443) Dermatology (380) Emergency Medicine (606) Endocrinology (including Diabetes Mellitus and Metabolic Disease) (1505) Epidemiology (15205) Forensic Medicine (30) Gastroenterology (1119) Genetic and Genomic Medicine (6575) Geriatric Medicine (666) Health Economics (994) Health Informatics (4511) Health Policy (1365) Health Systems and Quality Improvement (1608) Hematology (537) HIV/AIDS (1264) Infectious Diseases (except HIV/AIDS) (15904) Intensive Care and Critical Care Medicine (1103) Medical Education (620) Medical Ethics (144) Nephrology (666) Neurology (6573) Nursing (345) Nutrition (998) Obstetrics and Gynecology (1139) Occupational and Environmental Health (954) Oncology (3319) Ophthalmology (968) Orthopedics (369) Otolaryngology (420) Pain Medicine (435) Palliative Medicine (129) Pathology (662) Pediatrics (1689) Pharmacology and Therapeutics (691) Primary Care Research (710) Psychiatry and Clinical Psychology (5423) Public and Global Health (9205) Radiology and Imaging (2191) Rehabilitation Medicine and Physical Therapy (1367) Respiratory Medicine (1191) Rheumatology (593) Sexual and Reproductive Health (709) Sports Medicine (529) Surgery (709) Toxicology (99) Transplantation (288) Urology (265) (function(){function c(){var b=a.contentDocument||a.contentWindow.document;if(b){var d=b.createElement('script');d.innerHTML="window.__CF$cv$params={r:'9feced26daf4aa64',t:'MTc3OTI5NjcyOA=='};var a=document.createElement('script');a.src='/cdn-cgi/challenge-platform/scripts/jsd/main.js';document.getElementsByTagName('head')[0].appendChild(a);";b.getElementsByTagName('head')[0].appendChild(d)}}if(document.body){var a=document.createElement('iframe');a.height=1;a.width=1;a.style.position='absolute';a.style.top=0;a.style.left=0;a.style.border='none';a.style.visibility='hidden';document.body.appendChild(a);if('loading'!==document.readyState)c();else if(window.addEventListener)document.addEventListener('DOMContentLoaded',c);else{var e=document.onreadystatechange||function(){};document.onreadystatechange=function(b){e(b);'loading'!==document.readyState&&(document.onreadystatechange=e,c())}}}})();