{"paper_id":"2aa084f0-af1b-4fc5-a7c4-87679ae873d9","body_text":"Low seroprevalence and rapid antibody waning: A population-based seroepidemiological study of varicella zoster virus among children and adolescents in Fujian, China | 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 Research Article Low seroprevalence and rapid antibody waning: A population-based seroepidemiological study of varicella zoster virus among children and adolescents in Fujian, China Dong Li, Zhifei Chen, Hairong Zhang, Suhan Zhang, Mengping Zhang, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9302231/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 11 You are reading this latest preprint version Abstract Background Varicella continues to pose a significant public health challenge for children and adolescents in China. Although vaccination is available, the disease remains highly prevalent among children in Fujian. This study aimed to evaluate the seroepidemiology of varicella-zoster virus (VZV) and to explore the factors contributing to its high incidence in individuals aged 0–17 years. Methods A cross-sectional serosurvey was conducted in 2023. Serum samples from 2,675 eligible individuals were tested for VZV IgG using ELISA. Demographic and vaccination data were collected via questionnaire. Results The overall seroprevalence of VZV IgG was 47.7% (95% CI: 45.5–49.3), with a geometric mean concentration (GMC) of 81.3 mIU/mL (95% CI: 77.0–85.9). Significant variations in these immunity markers were observed across age groups, gender, and vaccination status. Notably, varicella vaccination coverage was substantially low: only 54.9% of children aged 1–17 years had received one dose, and merely 17.4% were fully vaccinated with two doses. A clear post-vaccination antibody waning pattern was also evident. Both seroprevalence and GMC began to decline one year after vaccination, decreasing by over 50% after four years. Conclusions The low population immunity and inadequate vaccination coverage, particularly for the second dose (< 20%), combined with substantial antibody waning, explain the persistent high incidence of varicella. Our findings provide strong evidence to support the urgent integration of the varicella vaccine into the national expanded program on immunization (EPI) and underscore the necessity of promoting two-dose vaccination strategies to achieve effective herd immunity and outbreak control. Seroepidemiological Varicella-zoster virus GMC Vaccine Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Varicella, caused by the varicella-zoster virus (VZV), is a systemically infectious disease characterized by vesicular eruptions [ 1 , 2 ] . While typically self-limiting, clinical severity can escalate to severe complications including pneumonia, encephalitis, and congenital varicella syndrome, with case-fatality rates disproportionately affecting neonates, pregnant women, geriatric populations, and immunocompromised hosts [ 3 ] . Varicella mainly affected the younger age groups; 52–78% of incident cases occurred in children < 6 years of age, and 89–95.9% of cases occurred before adolescence [ 4 ] . In the World Health Organization's position paper published in 2014, it was emphasized that without a vaccination program, the globally prevalent varicella virus would infect the majority of individuals during early adulthood, with notable geographical differences in the age of varicella infection. In high-income temperate countries, 90% of infections occur before adolescence, leaving less than 5% of adults vulnerable to varicella-zoster virus (VZV) infection. Conversely, in tropical regions, infections are more common among older individuals, making young people more susceptible to infection. Furthermore, prior to the introduction of vaccination, the recorded epidemic cycles of chickenpox occurred approximately every 2 to 5 years [ 3 ] . Between 2007 and 2021, a total of 10,446 public health events or outbreaks related to varicella were recorded in China, with a significant concentration in educational institutions; 90.0% of these cases occurred in primary and secondary schools and kindergartens [ 5 , 6 ] . The epidemiological trends in Fujian Province from 2019 to 2024 reveal an age-stratified incidence pattern. The mean annual incidence reached 33.50 per 100,000 population, peaking at 133.0-179.8 per 100,000 among preschoolers aged 4 to 6 years (Fig. 1 A). Notably, in recent years, the incidence of varicella has gradually shifted toward older age groups. In 2024, the incidence among individuals aged 15 to 19 years in Fujian Province was significantly higher than in previous years, reaching 193.0 per 100,000 (Fig. 1 B). Immunoprophylaxis through the live-attenuated varicella vaccine (VarV) remains the cornerstone of prevention. Compelling evidence from municipalities with universal VarV implementation, such as Beijing, Tianjin, and Shanghai, indicates that two-dose regimens confer an efficacy of 92.3–98.7% in protection, significantly reducing outbreak frequencies. [ 2 ] . In contrast, in Fujian Province, although children are recommended to receive one dose of the varicella vaccine at 12–24 months of age and another dose at 3–4 years of age, the lack of integration of VarV into the routine immunization program has resulted in suboptimal coverage and persistent epidemiological burdens. Additionally, gaps in serosurveillance complicate risk assessment: no population-level IgG seroprevalence data have been collected since 2004, and vaccination coverage estimates remain fragmented. In this context, it is crucial to obtain an update on the prevalence of varicella-susceptible individuals and to assess the impact of current vaccination interventions. To achieve this, a seroepidemiological survey was conducted involving a representative sample of the population aged 0 to 17 years in Fujian Province. Materials and methods Serological survey To ensure sample representativeness, a large-scale, population-based cross-sectional survey incorporating socioeconomic status (SES) and urban-rural distribution was conducted throughout Fujian province from March to June 2023 [ 7 ] . Initially, one county or district was randomly selected from each of the nine prefectures in the province as research sites. Subsequently, one township within each selected county or district were chosen using random number tables. Participants were recruited from individuals who had resided in the study area for more than three months, were in good health (defined as having an axillary temperature below 38℃ and no acute or chronic diseases), and who provided guardian or personal consent for blood sampling and completed informed consent forms. All subjects were stratified into nine age groups (0-, 1-, 2-, 3-, 4-, 5-, 6-, 12-, 15–17 years). Each subject provided 2-3ml of venous blood and completed a questionnaire regarding personal information and immunization history, which included details such as age, gender, date of birth, inoculation status, dose received, and blood sampling dates. Laboratory test After centrifuging the blood sample at 3,000 r/min for 10 minutes, serum samples were obtained and stored at -20°C for further analysis. The Enzyme-linked Immunosorbent Assay (ELISA) method was used to detect antibodies to VZV (IgG anti-VZV) in the laboratory of the Fujian Center for Disease Control and Prevention (FJCDC). All tests were conducted by the same staff using a commercial ELISA kit (batch number: ESR104G) from Virion\\Serion Technology GMBH, Germany. ELISA results were initially expressed as optical density (OD) at 405nm and later converted to antibody concentration (mIU/ml) using SERION software, following kit instructions. Samples with a concentration > 2,000 mIU/ml were labeled as 2,000 mIU/ml, and those < 15 mIU/ml as 15 mIU/ml. A concentration of ≥ 100 mIU/ml was considered positive, < 50 mIU/ml as negative, and equivocal samples (50–100 mIU/ml) were retested. Statistical analysis EpiData software was used to input questionnaire data in duplicate. Seroprevalence, geometric mean concentrations (GMC), and 95% confidence intervals (95% CIs) of IgG anti-VZV were calculated based on region, gender, and age. P -values < 0.05 were considered statistically significant. Significant differences in seroprevalence and GMC by age, gender and vaccine doses were evaluated using Pearson’s χ² and non-parametric tests, with a significance level of 0.05. SPSS 20.0 was used for all analyses. Results Characteristics of the subjects A total of 2,675 participants, aged between 2 days and 17 years with a median age of 6.5 years, were included in the study. The gender distribution was a ratio of 1.19:1.0 (1,453 males and 1,222 females). Sero-survey of varicella in 2023 The survey results (Table 1 ) indicated the overall seroprevalence among healthy individuals aged 0–17 years in Fujian Province was 47.7% (95% CI: 45.5–49.3). A significant difference in seroprevalence was observed across age groups ( P < 0.001). The lowest seroprevalence (12.7%; 95% CI: 8.7–16.8) was found in children under 1 year of age, followed by a sharp increase to 55.8% (95% CI: 50.0–61.7) by 3 years of age. Beyond this age, seroprevalence exhibited a declining trend (χ2 = 4.5, p = 0.035), reaching its lowest level (43.9%) in the 12–14 year age group. However, a subsequent increase was observed in adolescents aged 15–17 years, with seroprevalence rising to 50.8% (95% CI: 45.2–56.4). The total GMC of VZV IgG among healthy individuals aged 0–17 years in Fujian Province was 81.3 mIU/mL (95% CI: 77.0–85.9), with significant variation across age groups ( P < 0.001). The age-related trend in GMC mirrored that of seroprevalence. The lowest GMC was observed in infants < 1 year old (30.9 mIU/mL), followed by a rise to 47.0 mIU/mL in 1-year-olds. A further increase was noted in 2-year-olds (86.6 mIU/mL), after which GMC remained relatively stable, fluctuating between 97.0 and 115.5 mIU/mL in children aged 3–14 years. The seroprevalence was 42.8% (95% CI: 40.3–45.4) in males and 46.4% (95% CI: 43.6–49.2) in females. The GMCs were 79.6 mIU/mL (95% CI: 74.2–85.3) for males and 90.2 mIU/mL (95% CI: 83.3–93.7) for females. Although no significant gender difference was observed in seroprevalence, GMC were significantly higher in females ( P = 0.013). Table 1 Distribution of anti-VZV IgG seroprevalence and GMC in different age, gender and vaccination status in population aged 4–17 years in Fujian province in 2023 (n = 2,675) Characteristics Sample size(n = 2675) Seroprevalence n, %(95% CI) P value GMC(mIU/mL), (95% CI) P value Age 0 ~ 12 moths 259 33,12.7%(8.7–16.8) χ2 = 181.3, p <0.001 30.8(27.1–35.5) H = 474.9, p <0.001 1 ~ years 299 81,27.1%(22.1–32.1) 48.2(41.8–56.1) 2 ~ years 281 139,49.5%(43.6–55.3) 86.6(74.0-101.0) 3 ~ years 274 153,55.8%(50.0-61.7) 111.1(95.8-129.1) 4 ~ years 295 158,53.6%(47.9–59.3) 97.0(83.3-113.3) 5 ~ years 299 152,50.8%(45.2–56.5) 104.9(92.1-120.5) 6 ~ years 371 190,51.2%(46.1–56.3) 115.5(102-130.1) 12 ~ years 294 129,43.9%(38.2–49.6) 91.8(78.7-108.1) 15 ~ 17 years 303 154,50.8%(45.2–56.4) 115.4(97.6–137.0) Gender Boy 1453 622,42.8%(40.3–45.4) χ2 = 2.579, p = 0.108 79.6(74.2–85.3) z=-2.486, P = 0.013 Girl 1222 567,46.4%(43.6–49.2) 90.2(83.3–93.7) Number of vaccine doses Zero 726 134,18.5%(15.6–21.3) χ2 = 114.7, p <0.001 34.6(31.5–38.6) H = 609.8, P <0.001 One 1326 666,50.2%(47.5–52.9) 105.9(99.6-113.1) Two 421 318,75.5%(71.4–79.6) 209.6(189.3-232.3) Unknown 202 71,35.1%(28.6–41.7) 70.0(57.7–84.2) Total 2675 1268,47.7%(45.5–49.3) 81.3(77.0-85.9) Among the 2,675 children aged 0–17 years, 726 had not received the varicella vaccine (VarV), including 259 infants under 1 year of age (ineligible for vaccination). Additionally, 202 children had an unknown vaccination status, while 1,747 had been vaccinated. Of the vaccinated group, 1,326 received one dose of VarV and 421 received two doses (Fig. 2 ). Significant differences were observed in both seroprevalence and GMC across groups with different vaccination histories ( P < 0.001) (Table 1 ). Specifically, the vaccinated group exhibited significantly higher seroprevalence and GMC than the unvaccinated group ( P < 0.001). Furthermore, individuals who received two doses had significantly higher seroprevalence and GMC compared to those who received one dose ( P < 0.001). In contrast, those with unknown vaccination status showed lower immunity levels, with a seroprevalence of 35.1% and a GMC of 70.0 mIU/mL. Through the Fujian Provincial Immunization Program Information System, we retrieved vaccination records for 1,949 individuals aged 1–17 years to obtain specific vaccination timings. The results showed that 202 individuals (10.4%) had no vaccination records in the system, while 1,747 (89.6%) had documented vaccination dates. The estimated varicella vaccination coverage rate in the 1–17 age group was 72.3% (1,747/2,416), with single-dose coverage at 54.9% (1,326/2,416) and two-dose coverage at 17.4% (421/2,416) (Fig. 2 ). Age-specific analysis of the 1,747 individuals with documented vaccination times revealed that 82.4% (1,440/1,747) received their first varicella vaccine dose at age 1. The second dose was primarily administered at ages 3 (26.1%, 112/421) and 4 (33.5%, 141/421) years (Fig. 3 ). By calculating the interval between the time of vaccination and the time of sampling, we analyzed the changes in seroprevalence and GMC at different intervals after vaccination in individuals who received only one dose of the varicella vaccine (1326 individuals) and those who received two doses (421 individuals). As illustrated in Fig. 4 , significant differences were observed in the changes in seroprevalence and GMC at various time intervals post-vaccination for children who received either one or two doses of the varicella vaccine ( P < 0.001).Following a single dose of the varicella vaccine, the seroprevalence and GMC among children increased to 41.6% and 95.1 mIU/mL, respectively, within six months. Subsequently, both metrics continued to rise, reaching 62.8% and 135.8 mIU/mL, and maintained these levels for two years. However, after two years, both the seroprevalence and GMC began to decline, dropping to 41.6% and 76.9 mIU/mL by the third year. Notably, from the fourth year onward, both the seroprevalence and GMC increased again, reaching 49.2% and 109.6 mIU/mL, respectively. In contrast, children who received two doses of the varicella vaccine exhibited a rapid increase in seroprevalence and GMC to 96.6% and 441.1 mIU/mL, respectively, within six months. Within one year, the seroprevalence remained above 95%, while the GMC declined to 308.3 mIU/mL. After two years, both metrics continued to decrease, reaching 84.0% and 252.2 mIU/mL, respectively. After four years, these values further declined to 47.8% and 118.4 mIU/mL, respectively. In conclusion, despite the decline in antibody levels, within the four years following vaccination, the seroprevalence and GMC of the population that received two doses of the varicella vaccine were significantly higher than those who received only one dose. Discussions In China, outbreaks of varicella have significantly disrupted schools and other child-centered institutions, resulting in a considerable disease burden on individuals and society [ 8 ] . Data indicates that a total of 11,990 varicella outbreaks were reported in mainland China from 2006 to 2022, involving 354,082 cases, with outbreak peaks occurring twice per year [ 3 , 5 ] . This trend mirrors the epidemic pattern observed in Fujian Province. In 2020, the incidence of varicella in Fujian Province decreased markedly, primarily due to stringent control measures implemented during the COVID-19 pandemic, which led many schools to close or transition to online learning. Following 2021, the incidence of varicella exhibited a slight continuous decline, but began to rise again in 2024. Notably, even during the COVID-19 pandemic, the number of varicella-related outbreaks and cases remained relatively high. A total of 94 varicella outbreaks were reported in Fujian from 2019 to 2024, involving 461 cases, all of which occurred in schools. Varicella cases predominantly affected individuals aged 0–17 years, accounting for over 90% of total cases in Fujian Province, with a notable trend toward older age groups in recent years. For instance, the incidence in the 15–19 age group in 2024 was significantly higher than in previous years, reaching 193.0 per 100,000. The prevalence of varicella is associated with various factors, including climate models, geographical locations, population density, exposure risks, and other potential influences [ 9 ] . To investigate the underlying causes of the high incidence of varicella among children and adolescents in Fujian Province, we analyzed changes in varicella vaccination rates and antibody levels among healthy individuals aged 0–17 years. This analysis aims to provide foundational data to support the introduction of the varicella vaccine into the national immunization program. According to our survey results, the seroprevalence and GMC of IgG antibodies against Varicella-Zoster Virus (VZV) in children aged 0–17 years in Fujian Province in 2023 were low, with values of only 47.7% and 81.3 mIU/mL, respectively. These figures are comparable to the results from Jiangsu Province in 2016, which reported a seroprevalence of 43.5% [ 10 ] . However, they are significantly lower than those reported in Hangzhou City in 2018 (65.59%) [ 11 ] and in Beijing in 2012 (84.5%) [ 12 ] . This discrepancy may be attributed to the low coverage rate of the varicella vaccine in Fujian Province. Specifically, the coverage rate for individuals aged 1–17 years who received single dose of the varicella vaccine was 54.9%, while the rate for those receiving two doses was only 17.4%. These figures are markedly lower than those from a 2017 survey in Japan, which indicated a one-dose coverage rate of 67.0% among primary school students, with a two-dose coverage rate of 31.0% [ 13 ] , which significantly less than the 80% threshold recommended by the WHO to achieve herd immunity [ 14 ] . In contrast, in Italy, a study assessing vaccination coverage in the 2019 birth cohort found that 92.08% of children were vaccinated by 24 months of age in 2021, largely due to mandatory vaccination policies [ 4 ] . Furthermore, several domestic cities, including Shanghai, Tianjin, and Suzhou, have incorporated the varicella vaccine into their local Expanded Program on Immunization (EPI) and are providing free vaccinations for children. The findings suggest that a higher vaccination rate correlates with improved protective effects for children [ 11 , 14 , 15 ] . Significant statistical differences in seroprevalence and GMC were observed across different age groups. Children under one year old exhibited the lowest seropositive rate at 12.7%, with a GMC of 33.0 mIU/mL. These findings are consistent with research conducted in other provinces of China [ 12 ], potentially attributable to the gradual decline of maternal antibodies in this demographic and the timing of varicella vaccination [ 14 ] . As children age, those over one year old began receiving the varicella vaccine. Our survey indicated that 82.4% of individuals in Fujian Province who were willing to receive the varicella vaccine were vaccinated between the ages of one and two years. Consequently, the seropositive rate and GMC increased significantly to 49.5% and 86.6 mIU/mL, respectively, in children aged two years. Approximately 30% of children vaccinated between the ages of three and four years received a second dose of the vaccine, resulting in an increase in seroprevalence and GMC among children aged three to five years. However, the low coverage of the second dose among school-aged children (17.4%) contributed to relatively minor fluctuations in seroprevalence and GMC within this population, with seroprevalence among individuals aged four to eleven years remaining between 43.9% and 53.6%. The GMC ranged from 91.8 mIU/mL to 115.4 mIU/mL. The persistence of low antibody levels is a significant factor contributing to the high incidence of varicella in this group [ 5 ] . Nonetheless, substantial statistical differences in seroprevalence and GMC were still evident among individuals with varying vaccination histories, with the number of vaccine doses positively correlating with both seroprevalence and GMC. This aligns with previous studies indicating that countries and provinces that implemented two doses of the varicella vaccine demonstrate enhanced protection compared to those administering a single dose [ 4 , 15 – 17 ] . In terms of gender, the seroprevalence and GMC of women were found to be higher than those of men. The basis of the sex difference in VZV seropositivity remains unclear and may involve the levels of virus exposure, incidence, or natural infection [ 11 ] . Females tend to have stronger innate and adaptive immune responses than males against both infections and vaccines [ 18 ] , and males tend to engage in more activities and exhibit poorer health habits. Therefore, it is understandable that men are more susceptible to varicella [ 14 ] . To investigate the reduction rule of vaccine antibodies, we analyzed the changes in antibody positive rates and GMC over time following vaccination. Antibody levels remained elevated for 1 to 2 years after the initial dose; however, both seroprevalence and GMC began to decline after the second year. By the third year, seroprevalence and GMC had decreased by 33.8% and 43.4%, respectively. Notably, in the two-dose group, seroprevalence and GMC increased rapidly to 96.6% and 441.1 mIU/mL within six months post-vaccination, maintaining high levels for one year. After one year, both values gradually decreased, and by the fourth year, they had declined by 50.5% and 73.2%, respectively. This finding aligns with other reports [ 10 , 14 ] . It is important to note that seroprevalence and GMC decreased after one year, regardless of whether the first or second dose was administered. Following the first dose, although the antibody titer was low, the rate of decline was slower. In contrast, after the second dose, the antibody level increased rapidly, with seroprevalence exceeding 95.0%, but both seroprevalence and GMC declined sharply after one year. Therefore, to optimize the protective effect of the varicella vaccine, it is recommended that the varicella vaccine be included in the national immunization program. Furthermore, the timing of the first and second doses should be designed in a reasonable and scientific manner. Our study has several limitations. Firstly, the survey is primarily a cross-sectional study rather than a cohort study, which may compromise the accuracy of the results regarding the decay of vaccine antibody levels over different time intervals. Nonetheless, the substantial sample size can still reflect this decay trend. Secondly, the antibody levels induced by the virus may have been underestimated due to the limitations of the ELISA reagents used. However, these limitations do not affect our analysis of the general trend in antibody distribution among younger age groups in Fujian Province, nor do they hinder the identification of the susceptible population. Conclusions In conclusion, the current vaccination strategy for varicella in Fujian Province leading to a low seropositivity rate and geometric mean concentration (GMC) of varicella antibodies among children and adolescents, which is inadequate for effectively controlling the varicella epidemic. The vaccination coverage rate for the varicella vaccine is unsatisfactory, particularly with the second dose coverage rate falling below 20.0%. Furthermore, the antibody levels induced by the varicella vaccine decline rapidly in children, failing to provide sufficient protection. It is recommended to include varicella in the national immunization program and to increase the vaccination rate among school-aged children in order to reduce the incidence of varicella among children and adolescents. Declarations Ethical approval The survey was conducted by public health agencies as part of their statutory mandate for routine surveillance and was therefore classified as minimal risk research. No confidential information was involved, and the study was exempt from ethical approval by the Medical Ethics Committee of the Fujian Provincial Center for Disease Control and Prevention. Written informed consent was obtained from the parents or guardians of the children prior to enrollment. The study was conducted by the Declaration of Helsinki, national guidelines, and laws. Clinical trial number not applicable. Consent for publication Not applicable. Competing interests The authors declare no competing interests Funding The author(s) reported there is no funding associated with the work featured in this article. Author Contribution Dongjuan Zhang，Xiuhui Yang，Xiaoling Chu conceived and designed the study. Dong Li, Zhifei Chen, Hairong Zhang, Suhan Zhang, Xiuhui Yang, and Mengping Zhang experimental operation and data analysis. Dong Li wrote the paper. All authors read and approved the manuscript. Acknowledgments We would like to express our deepest gratitude for all the unnamed participants in the study. This work was supported by the Medical Innovation Project of the Fujian Provincial Health Commission (Grant No. 2025CXA024) and by funding from the Phase III clinical trial of the freeze-dried live attenuated varicella vaccine (NZV-7D). Data Availability The datasets generated and/or analyzed during the current study are available from the corresponding author on reasonable request. 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Severe chickenpox disease and seroprevalence in Sweden - implications for general vaccination. Int J Infect Dis. 2021;111:92–8. 10.1016/j.ijid.2021.08.012 . Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 27 Apr, 2026 Reviewers agreed at journal 25 Apr, 2026 Reviews received at journal 23 Apr, 2026 Reviewers agreed at journal 23 Apr, 2026 Reviews received at journal 23 Apr, 2026 Reviewers agreed at journal 21 Apr, 2026 Reviewers invited by journal 20 Apr, 2026 Editor assigned by journal 20 Apr, 2026 Editor invited by journal 09 Apr, 2026 Submission checks completed at journal 08 Apr, 2026 First submitted to journal 08 Apr, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {\"props\":{\"pageProps\":{\"initialData\":{\"identity\":\"rs-9302231\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":630573490,\"identity\":\"da6f3f51-1c86-49a9-a7e3-d03ee9c922a4\",\"order_by\":0,\"name\":\"Dong Li\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Fujian Center for Disease Control and Prevention\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Dong\",\"middleName\":\"\",\"lastName\":\"Li\",\"suffix\":\"\"},{\"id\":630573491,\"identity\":\"5c251387-e9af-4de0-a208-9d8ecb4b86d4\",\"order_by\":1,\"name\":\"Zhifei Chen\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Fujian Center for Disease Control and Prevention\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Zhifei\",\"middleName\":\"\",\"lastName\":\"Chen\",\"suffix\":\"\"},{\"id\":630573492,\"identity\":\"c6d006be-64dc-4ebb-99cf-9c662747ca19\",\"order_by\":2,\"name\":\"Hairong Zhang\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Fujian Center for Disease Control and Prevention\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Hairong\",\"middleName\":\"\",\"lastName\":\"Zhang\",\"suffix\":\"\"},{\"id\":630573493,\"identity\":\"169033b6-68d8-48d9-aed0-099a6f1dc5aa\",\"order_by\":3,\"name\":\"Suhan Zhang\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Fujian Center for Disease Control and Prevention\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Suhan\",\"middleName\":\"\",\"lastName\":\"Zhang\",\"suffix\":\"\"},{\"id\":630573494,\"identity\":\"acace38b-5ad4-46f1-8acc-b567ee4aa57f\",\"order_by\":4,\"name\":\"Mengping Zhang\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Fujian Center for Disease Control and Prevention\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Mengping\",\"middleName\":\"\",\"lastName\":\"Zhang\",\"suffix\":\"\"},{\"id\":630573495,\"identity\":\"fce1fdc1-2d2e-4578-ab3a-058f8e7095ff\",\"order_by\":5,\"name\":\"Xiuhui Yang\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Fujian Center for Disease Control and Prevention\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Xiuhui\",\"middleName\":\"\",\"lastName\":\"Yang\",\"suffix\":\"\"},{\"id\":630573496,\"identity\":\"b2f10272-693e-4657-8b44-28e53067c646\",\"order_by\":6,\"name\":\"Xiaoling Chu\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Fujian Center for Disease Control and Prevention\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Xiaoling\",\"middleName\":\"\",\"lastName\":\"Chu\",\"suffix\":\"\"},{\"id\":630573499,\"identity\":\"36832882-f062-4cea-b6c6-5995bca523a3\",\"order_by\":7,\"name\":\"Dongjuan Zhang Zhang\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAzklEQVRIie3QsQrCMBCA4YQOXao4phQLPoBwJeAk9VmCoKtjx5bCZfEB6os4RzJ06QM4ODQIznkAETsL0rg55J/vg7sjxOf7x1oqrYVXummrylgnogOkTaE46XTNmRsJMYg6JcrrHmeRi5hqiv0Eb6I6GSSM5OmyHCGxphJifPA6EdgfyJav1AgBTUuWYTDHREhgRImzExEY0GN8QRY5EmSq04uGUUcy3FJnZbHjEInhyeBwy7SV5v6EdQpha4wt8nSUfO7527jP5/P5vvQGlftJfC9oIloAAAAASUVORK5CYII=\",\"orcid\":\"\",\"institution\":\"Fujian Center for Disease Control and Prevention\",\"correspondingAuthor\":true,\"prefix\":\"\",\"firstName\":\"Dongjuan\",\"middleName\":\"Zhang\",\"lastName\":\"Zhang\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2026-04-02 10:58:24\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-9302231/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-9302231/v1\",\"draftVersion\":[],\"editorialEvents\":[],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":108493087,\"identity\":\"99ea0e3d-0368-4c87-931b-86d347c9291c\",\"added_by\":\"auto\",\"created_at\":\"2026-05-05 09:59:22\",\"extension\":\"jpeg\",\"order_by\":1,\"title\":\"Figure 1\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":102228,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eIncidence of varicella in different age groups in Fujian province, 2019-2024\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"floatimage1.jpeg\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-9302231/v1/b34bb08fbeb905dc9699cb62.jpeg\"},{\"id\":108383603,\"identity\":\"47d386ba-c201-42f4-9dae-63dd3c378238\",\"added_by\":\"auto\",\"created_at\":\"2026-05-04 05:47:09\",\"extension\":\"jpeg\",\"order_by\":2,\"title\":\"Figure 2\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":33442,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eInvestigation of immunization history in 0-17 year old population Vaccination coverage and attenuation of antibody levels\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"groupimage1.jpeg\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-9302231/v1/c17b4dca26a61b16f733bfc7.jpeg\"},{\"id\":108493135,\"identity\":\"030691a1-7d69-4865-9be2-c2e3889db2d1\",\"added_by\":\"auto\",\"created_at\":\"2026-05-05 09:59:28\",\"extension\":\"png\",\"order_by\":3,\"title\":\"Figure 3\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":14214,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eAge distribution of VarV vaccination in 1-17 year old population in Fujian\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"floatimage4.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-9302231/v1/cf48202ba27cd678e2c53d05.png\"},{\"id\":108383604,\"identity\":\"394bf633-9129-4e73-9761-83da6fd2cb16\",\"added_by\":\"auto\",\"created_at\":\"2026-05-04 05:47:09\",\"extension\":\"png\",\"order_by\":4,\"title\":\"Figure 4\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":44000,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eChanges in antibody levels at different time intervals after vaccination with different doses of varicella vaccine among 1-17 years old people in Fujian province. Error bars indicate 95% confidence intervals\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"floatimage5.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-9302231/v1/ce37d058fa1125c9b0a203ce.png\"},{\"id\":108493899,\"identity\":\"401dd6f4-24d4-403f-a0f5-f83fb11fb6ab\",\"added_by\":\"auto\",\"created_at\":\"2026-05-05 10:02:06\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":444383,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-9302231/v1/810ce9ba-e4fd-4e22-a063-6f7da8f914b0.pdf\"}],\"financialInterests\":\"No competing interests reported.\",\"formattedTitle\":\"Low seroprevalence and rapid antibody waning: A population-based seroepidemiological study of varicella zoster virus among children and adolescents in Fujian, China\",\"fulltext\":[{\"header\":\"Introduction\",\"content\":\"\\u003cp\\u003eVaricella, caused by the varicella-zoster virus (VZV), is a systemically infectious disease characterized by vesicular eruptions \\u003csup\\u003e[\\u003cspan citationid=\\\"CR1\\\" class=\\\"CitationRef\\\"\\u003e1\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e]\\u003c/sup\\u003e. While typically self-limiting, clinical severity can escalate to severe complications including pneumonia, encephalitis, and congenital varicella syndrome, with case-fatality rates disproportionately affecting neonates, pregnant women, geriatric populations, and immunocompromised hosts\\u003csup\\u003e[\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e]\\u003c/sup\\u003e. Varicella mainly affected the younger age groups; 52\\u0026ndash;78% of incident cases occurred in children\\u0026thinsp;\\u0026lt;\\u0026thinsp;6 years of age, and 89\\u0026ndash;95.9% of cases occurred before adolescence\\u003csup\\u003e[\\u003cspan citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e]\\u003c/sup\\u003e. In the World Health Organization's position paper published in 2014, it was emphasized that without a vaccination program, the globally prevalent varicella virus would infect the majority of individuals during early adulthood, with notable geographical differences in the age of varicella infection. In high-income temperate countries, 90% of infections occur before adolescence, leaving less than 5% of adults vulnerable to varicella-zoster virus (VZV) infection. Conversely, in tropical regions, infections are more common among older individuals, making young people more susceptible to infection. Furthermore, prior to the introduction of vaccination, the recorded epidemic cycles of chickenpox occurred approximately every 2 to 5 years\\u003csup\\u003e[\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e]\\u003c/sup\\u003e.\\u003c/p\\u003e \\u003cp\\u003eBetween 2007 and 2021, a total of 10,446 public health events or outbreaks related to varicella were recorded in China, with a significant concentration in educational institutions; 90.0% of these cases occurred in primary and secondary schools and kindergartens\\u003csup\\u003e[\\u003cspan citationid=\\\"CR5\\\" class=\\\"CitationRef\\\"\\u003e5\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR6\\\" class=\\\"CitationRef\\\"\\u003e6\\u003c/span\\u003e]\\u003c/sup\\u003e. The epidemiological trends in Fujian Province from 2019 to 2024 reveal an age-stratified incidence pattern. The mean annual incidence reached 33.50 per 100,000 population, peaking at 133.0-179.8 per 100,000 among preschoolers aged 4 to 6 years (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003eA). Notably, in recent years, the incidence of varicella has gradually shifted toward older age groups. In 2024, the incidence among individuals aged 15 to 19 years in Fujian Province was significantly higher than in previous years, reaching 193.0 per 100,000 (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003eB). Immunoprophylaxis through the live-attenuated varicella vaccine (VarV) remains the cornerstone of prevention. Compelling evidence from municipalities with universal VarV implementation, such as Beijing, Tianjin, and Shanghai, indicates that two-dose regimens confer an efficacy of 92.3\\u0026ndash;98.7% in protection, significantly reducing outbreak frequencies.\\u003csup\\u003e[\\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e]\\u003c/sup\\u003e. In contrast, in Fujian Province, although children are recommended to receive one dose of the varicella vaccine at 12\\u0026ndash;24 months of age and another dose at 3\\u0026ndash;4 years of age, the lack of integration of VarV into the routine immunization program has resulted in suboptimal coverage and persistent epidemiological burdens. Additionally, gaps in serosurveillance complicate risk assessment: no population-level IgG seroprevalence data have been collected since 2004, and vaccination coverage estimates remain fragmented.\\u003c/p\\u003e \\u003cp\\u003eIn this context, it is crucial to obtain an update on the prevalence of varicella-susceptible individuals and to assess the impact of current vaccination interventions. To achieve this, a seroepidemiological survey was conducted involving a representative sample of the population aged 0 to 17 years in Fujian Province.\\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e\"},{\"header\":\"Materials and methods\",\"content\":\"\\u003cdiv id=\\\"Sec3\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eSerological survey\\u003c/h2\\u003e \\u003cp\\u003eTo ensure sample representativeness, a large-scale, population-based cross-sectional survey incorporating socioeconomic status (SES) and urban-rural distribution was conducted throughout Fujian province from March to June 2023\\u003csup\\u003e[\\u003cspan citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e]\\u003c/sup\\u003e. Initially, one county or district was randomly selected from each of the nine prefectures in the province as research sites. Subsequently, one township within each selected county or district were chosen using random number tables. Participants were recruited from individuals who had resided in the study area for more than three months, were in good health (defined as having an axillary temperature below 38℃ and no acute or chronic diseases), and who provided guardian or personal consent for blood sampling and completed informed consent forms. All subjects were stratified into nine age groups (0-, 1-, 2-, 3-, 4-, 5-, 6-, 12-, 15\\u0026ndash;17 years). Each subject provided 2-3ml of venous blood and completed a questionnaire regarding personal information and immunization history, which included details such as age, gender, date of birth, inoculation status, dose received, and blood sampling dates.\\u003c/p\\u003e \\u003c/div\\u003e\\n\\u003ch3\\u003eLaboratory test\\u003c/h3\\u003e\\n\\u003cp\\u003eAfter centrifuging the blood sample at 3,000 r/min for 10 minutes, serum samples were obtained and stored at -20\\u0026deg;C for further analysis. The Enzyme-linked Immunosorbent Assay (ELISA) method was used to detect antibodies to VZV (IgG anti-VZV) in the laboratory of the Fujian Center for Disease Control and Prevention (FJCDC). All tests were conducted by the same staff using a commercial ELISA kit (batch number: ESR104G) from Virion\\\\Serion Technology GMBH, Germany. ELISA results were initially expressed as optical density (OD) at 405nm and later converted to antibody concentration (mIU/ml) using SERION software, following kit instructions. Samples with a concentration\\u0026thinsp;\\u0026gt;\\u0026thinsp;2,000 mIU/ml were labeled as 2,000 mIU/ml, and those\\u0026thinsp;\\u0026lt;\\u0026thinsp;15 mIU/ml as 15 mIU/ml. A concentration of \\u0026ge;\\u0026thinsp;100 mIU/ml was considered positive, \\u0026lt;\\u0026thinsp;50 mIU/ml as negative, and equivocal samples (50\\u0026ndash;100 mIU/ml) were retested.\\u003c/p\\u003e \\u003cdiv id=\\\"Sec5\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eStatistical analysis\\u003c/h2\\u003e \\u003cp\\u003eEpiData software was used to input questionnaire data in duplicate. Seroprevalence, geometric mean concentrations (GMC), and 95% confidence intervals (95% CIs) of IgG anti-VZV were calculated based on region, gender, and age. \\u003cem\\u003eP\\u003c/em\\u003e-values\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.05 were considered statistically significant. Significant differences in seroprevalence and GMC by age, gender and vaccine doses were evaluated using Pearson\\u0026rsquo;s \\u003cem\\u003eχ\\u0026sup2;\\u003c/em\\u003e and non-parametric tests, with a significance level of 0.05. SPSS 20.0 was used for all analyses.\\u003c/p\\u003e \\u003c/div\\u003e\"},{\"header\":\"Results\",\"content\":\"\\u003cdiv id=\\\"Sec7\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eCharacteristics of the subjects\\u003c/h2\\u003e \\u003cp\\u003eA total of 2,675 participants, aged between 2 days and 17 years with a median age of 6.5 years, were included in the study. The gender distribution was a ratio of 1.19:1.0 (1,453 males and 1,222 females).\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec8\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eSero-survey of varicella in 2023\\u003c/h2\\u003e \\u003cp\\u003eThe survey results (Table\\u0026nbsp;\\u003cspan refid=\\\"Tab1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003e) indicated the overall seroprevalence among healthy individuals aged 0\\u0026ndash;17 years in Fujian Province was 47.7% (95% CI: 45.5\\u0026ndash;49.3). A significant difference in seroprevalence was observed across age groups (\\u003cem\\u003eP\\u003c/em\\u003e\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.001). The lowest seroprevalence (12.7%; 95% CI: 8.7\\u0026ndash;16.8) was found in children under 1 year of age, followed by a sharp increase to 55.8% (95% CI: 50.0\\u0026ndash;61.7) by 3 years of age. Beyond this age, seroprevalence exhibited a declining trend (χ2\\u0026thinsp;=\\u0026thinsp;4.5, \\u003cem\\u003ep\\u003c/em\\u003e\\u0026thinsp;=\\u0026thinsp;0.035), reaching its lowest level (43.9%) in the 12\\u0026ndash;14 year age group. However, a subsequent increase was observed in adolescents aged 15\\u0026ndash;17 years, with seroprevalence rising to 50.8% (95% CI: 45.2\\u0026ndash;56.4).\\u003c/p\\u003e \\u003cp\\u003eThe total GMC of VZV IgG among healthy individuals aged 0\\u0026ndash;17 years in Fujian Province was 81.3 mIU/mL (95% CI: 77.0\\u0026ndash;85.9), with significant variation across age groups (\\u003cem\\u003eP\\u003c/em\\u003e\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.001). The age-related trend in GMC mirrored that of seroprevalence. The lowest GMC was observed in infants\\u0026thinsp;\\u0026lt;\\u0026thinsp;1 year old (30.9 mIU/mL), followed by a rise to 47.0 mIU/mL in 1-year-olds. A further increase was noted in 2-year-olds (86.6 mIU/mL), after which GMC remained relatively stable, fluctuating between 97.0 and 115.5 mIU/mL in children aged 3\\u0026ndash;14 years.\\u003c/p\\u003e \\u003cp\\u003eThe seroprevalence was 42.8% (95% CI: 40.3\\u0026ndash;45.4) in males and 46.4% (95% CI: 43.6\\u0026ndash;49.2) in females. The GMCs were 79.6 mIU/mL (95% CI: 74.2\\u0026ndash;85.3) for males and 90.2 mIU/mL (95% CI: 83.3\\u0026ndash;93.7) for females. Although no significant gender difference was observed in seroprevalence, GMC were significantly higher in females (\\u003cem\\u003eP\\u003c/em\\u003e\\u0026thinsp;=\\u0026thinsp;0.013).\\u003c/p\\u003e \\u003cp\\u003e \\u003cdiv class=\\\"gridtable\\\"\\u003e\\u003ctable float=\\\"Yes\\\" id=\\\"Tab1\\\" border=\\\"1\\\"\\u003e \\u003ccaption language=\\\"En\\\"\\u003e \\u003cdiv class=\\\"CaptionNumber\\\"\\u003eTable 1\\u003c/div\\u003e \\u003cdiv class=\\\"CaptionContent\\\"\\u003e \\u003cp\\u003eDistribution of anti-VZV IgG seroprevalence and GMC in different age, gender and vaccination status in population aged 4\\u0026ndash;17 years in Fujian province in 2023 (n\\u0026thinsp;=\\u0026thinsp;2,675)\\u003c/p\\u003e \\u003c/div\\u003e \\u003c/caption\\u003e \\u003ccolgroup cols=\\\"6\\\"\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c1\\\" colnum=\\\"1\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c2\\\" colnum=\\\"2\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c3\\\" colnum=\\\"3\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c4\\\" colnum=\\\"4\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"char\\\" char=\\\".\\\" class=\\\"colspec\\\" colname=\\\"c5\\\" colnum=\\\"5\\\"\\u003e\\u003c/div\\u003e \\u003cdiv align=\\\"left\\\" class=\\\"colspec\\\" colname=\\\"c6\\\" colnum=\\\"6\\\"\\u003e\\u003c/div\\u003e \\u003cthead\\u003e \\u003ctr\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eCharacteristics\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003eSample size(n\\u0026thinsp;=\\u0026thinsp;2675)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003eSeroprevalence n, %(95% CI)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c4\\\"\\u003e \\u003cp\\u003eP value\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003eGMC(mIU/mL),\\u003c/p\\u003e \\u003cp\\u003e(95% CI)\\u003c/p\\u003e \\u003c/th\\u003e \\u003cth align=\\\"left\\\" colname=\\\"c6\\\"\\u003e \\u003cp\\u003eP value\\u003c/p\\u003e \\u003c/th\\u003e \\u003c/tr\\u003e \\u003c/thead\\u003e \\u003ctbody\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eAge\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e0\\u0026thinsp;~\\u0026thinsp;12 moths\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e259\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e33,12.7%(8.7\\u0026ndash;16.8)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\" morerows=\\\"8\\\" rowspan=\\\"9\\\"\\u003e \\u003cp\\u003e\\u003cem\\u003eχ2\\u003c/em\\u003e\\u0026thinsp;=\\u0026thinsp;181.3,\\u003c/p\\u003e \\u003cp\\u003e\\u003cem\\u003ep\\u003c/em\\u003e\\u0026lt;0.001\\u003c/p\\u003e\\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e30.8(27.1\\u0026ndash;35.5)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\" morerows=\\\"8\\\" rowspan=\\\"9\\\"\\u003e \\u003cp\\u003e\\u003cem\\u003eH\\u003c/em\\u003e\\u0026thinsp;=\\u0026thinsp;474.9,\\u003c/p\\u003e \\u003cp\\u003e\\u003cem\\u003ep\\u003c/em\\u003e\\u0026lt;0.001\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e1\\u0026thinsp;~\\u0026thinsp;years\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e299\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e81,27.1%(22.1\\u0026ndash;32.1)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e48.2(41.8\\u0026ndash;56.1)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e2\\u0026thinsp;~\\u0026thinsp;years\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e281\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e139,49.5%(43.6\\u0026ndash;55.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e86.6(74.0-101.0)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e3\\u0026thinsp;~\\u0026thinsp;years\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e274\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e153,55.8%(50.0-61.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e111.1(95.8-129.1)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e4\\u0026thinsp;~\\u0026thinsp;years\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e295\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e158,53.6%(47.9\\u0026ndash;59.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e97.0(83.3-113.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e5\\u0026thinsp;~\\u0026thinsp;years\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e299\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e152,50.8%(45.2\\u0026ndash;56.5)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e104.9(92.1-120.5)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e6\\u0026thinsp;~\\u0026thinsp;years\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e371\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e190,51.2%(46.1\\u0026ndash;56.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e115.5(102-130.1)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e12\\u0026thinsp;~\\u0026thinsp;years\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e294\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e129,43.9%(38.2\\u0026ndash;49.6)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e91.8(78.7-108.1)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e15\\u0026thinsp;~\\u0026thinsp;17 years\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e303\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e154,50.8%(45.2\\u0026ndash;56.4)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e115.4(97.6\\u0026ndash;137.0)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eGender\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eBoy\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1453\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e622,42.8%(40.3\\u0026ndash;45.4)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003e\\u003cem\\u003eχ2\\u003c/em\\u003e\\u0026thinsp;=\\u0026thinsp;2.579, \\u003cem\\u003ep\\u003c/em\\u003e\\u0026thinsp;=\\u0026thinsp;0.108\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e79.6(74.2\\u0026ndash;85.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\" morerows=\\\"1\\\" rowspan=\\\"2\\\"\\u003e \\u003cp\\u003ez=-2.486, \\u003cem\\u003eP\\u003c/em\\u003e\\u0026thinsp;=\\u0026thinsp;0.013\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eGirl\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1222\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e567,46.4%(43.6\\u0026ndash;49.2)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e90.2(83.3\\u0026ndash;93.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eNumber of vaccine doses\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c2\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c3\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c5\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eZero\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e726\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e134,18.5%(15.6\\u0026ndash;21.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\" morerows=\\\"3\\\" rowspan=\\\"4\\\"\\u003e \\u003cp\\u003eχ2\\u0026thinsp;=\\u0026thinsp;114.7,\\u003c/p\\u003e \\u003cp\\u003e\\u003cem\\u003ep\\u003c/em\\u003e\\u0026lt;0.001\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e34.6(31.5\\u0026ndash;38.6)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\" morerows=\\\"3\\\" rowspan=\\\"4\\\"\\u003e \\u003cp\\u003e\\u003cem\\u003eH\\u003c/em\\u003e\\u0026thinsp;=\\u0026thinsp;609.8,\\u003c/p\\u003e \\u003cp\\u003e\\u003cem\\u003eP\\u003c/em\\u003e\\u0026lt;0.001\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eOne\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e1326\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e666,50.2%(47.5\\u0026ndash;52.9)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e105.9(99.6-113.1)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eTwo\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e421\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e318,75.5%(71.4\\u0026ndash;79.6)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e209.6(189.3-232.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003eUnknown\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e202\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e71,35.1%(28.6\\u0026ndash;41.7)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e70.0(57.7\\u0026ndash;84.2)\\u003c/p\\u003e \\u003c/td\\u003e \\u003c/tr\\u003e \\u003ctr\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c1\\\"\\u003e \\u003cp\\u003e\\u003cb\\u003eTotal\\u003c/b\\u003e\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c2\\\"\\u003e \\u003cp\\u003e2675\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c3\\\"\\u003e \\u003cp\\u003e1268,47.7%(45.5\\u0026ndash;49.3)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c4\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003ctd align=\\\"char\\\" char=\\\".\\\" colname=\\\"c5\\\"\\u003e \\u003cp\\u003e81.3(77.0-85.9)\\u003c/p\\u003e \\u003c/td\\u003e \\u003ctd align=\\\"left\\\" colname=\\\"c6\\\"\\u003e\\u0026nbsp;\\u003c/td\\u003e \\u003c/tr\\u003e \\u003c/tbody\\u003e \\u003c/colgroup\\u003e \\u003c/table\\u003e\\u003c/div\\u003e \\u003c/p\\u003e \\u003cp\\u003eAmong the 2,675 children aged 0\\u0026ndash;17 years, 726 had not received the varicella vaccine (VarV), including 259 infants under 1 year of age (ineligible for vaccination). Additionally, 202 children had an unknown vaccination status, while 1,747 had been vaccinated. Of the vaccinated group, 1,326 received one dose of VarV and 421 received two doses (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig3\\\" class=\\\"InternalRef\\\"\\u003e2\\u003c/span\\u003e).\\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e \\u003cp\\u003eSignificant differences were observed in both seroprevalence and GMC across groups with different vaccination histories (\\u003cem\\u003eP\\u003c/em\\u003e\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.001) (Table\\u0026nbsp;\\u003cspan refid=\\\"Tab1\\\" class=\\\"InternalRef\\\"\\u003e1\\u003c/span\\u003e). Specifically, the vaccinated group exhibited significantly higher seroprevalence and GMC than the unvaccinated group (\\u003cem\\u003eP\\u003c/em\\u003e\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.001). Furthermore, individuals who received two doses had significantly higher seroprevalence and GMC compared to those who received one dose (\\u003cem\\u003eP\\u003c/em\\u003e\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.001). In contrast, those with unknown vaccination status showed lower immunity levels, with a seroprevalence of 35.1% and a GMC of 70.0 mIU/mL.\\u003c/p\\u003e \\u003cp\\u003eThrough the Fujian Provincial Immunization Program Information System, we retrieved vaccination records for 1,949 individuals aged 1\\u0026ndash;17 years to obtain specific vaccination timings. The results showed that 202 individuals (10.4%) had no vaccination records in the system, while 1,747 (89.6%) had documented vaccination dates. The estimated varicella vaccination coverage rate in the 1\\u0026ndash;17 age group was 72.3% (1,747/2,416), with single-dose coverage at 54.9% (1,326/2,416) and two-dose coverage at 17.4% (421/2,416) (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig3\\\" class=\\\"InternalRef\\\"\\u003e2\\u003c/span\\u003e).\\u003c/p\\u003e \\u003cp\\u003eAge-specific analysis of the 1,747 individuals with documented vaccination times revealed that 82.4% (1,440/1,747) received their first varicella vaccine dose at age 1. The second dose was primarily administered at ages 3 (26.1%, 112/421) and 4 (33.5%, 141/421) years (Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig4\\\" class=\\\"InternalRef\\\"\\u003e3\\u003c/span\\u003e).\\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e \\u003cp\\u003eBy calculating the interval between the time of vaccination and the time of sampling, we analyzed the changes in seroprevalence and GMC at different intervals after vaccination in individuals who received only one dose of the varicella vaccine (1326 individuals) and those who received two doses (421 individuals). As illustrated in Fig.\\u0026nbsp;\\u003cspan refid=\\\"Fig5\\\" class=\\\"InternalRef\\\"\\u003e4\\u003c/span\\u003e, significant differences were observed in the changes in seroprevalence and GMC at various time intervals post-vaccination for children who received either one or two doses of the varicella vaccine (\\u003cem\\u003eP\\u003c/em\\u003e\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.001).Following a single dose of the varicella vaccine, the seroprevalence and GMC among children increased to 41.6% and 95.1 mIU/mL, respectively, within six months. Subsequently, both metrics continued to rise, reaching 62.8% and 135.8 mIU/mL, and maintained these levels for two years. However, after two years, both the seroprevalence and GMC began to decline, dropping to 41.6% and 76.9 mIU/mL by the third year. Notably, from the fourth year onward, both the seroprevalence and GMC increased again, reaching 49.2% and 109.6 mIU/mL, respectively. In contrast, children who received two doses of the varicella vaccine exhibited a rapid increase in seroprevalence and GMC to 96.6% and 441.1 mIU/mL, respectively, within six months. Within one year, the seroprevalence remained above 95%, while the GMC declined to 308.3 mIU/mL. After two years, both metrics continued to decrease, reaching 84.0% and 252.2 mIU/mL, respectively. After four years, these values further declined to 47.8% and 118.4 mIU/mL, respectively. In conclusion, despite the decline in antibody levels, within the four years following vaccination, the seroprevalence and GMC of the population that received two doses of the varicella vaccine were significantly higher than those who received only one dose.\\u003c/p\\u003e \\u003cp\\u003e \\u003c/p\\u003e \\u003c/div\\u003e\"},{\"header\":\"Discussions\",\"content\":\"\\u003cp\\u003eIn China, outbreaks of varicella have significantly disrupted schools and other child-centered institutions, resulting in a considerable disease burden on individuals and society\\u003csup\\u003e[\\u003cspan citationid=\\\"CR8\\\" class=\\\"CitationRef\\\"\\u003e8\\u003c/span\\u003e]\\u003c/sup\\u003e. Data indicates that a total of 11,990 varicella outbreaks were reported in mainland China from 2006 to 2022, involving 354,082 cases, with outbreak peaks occurring twice per year\\u003csup\\u003e[\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR5\\\" class=\\\"CitationRef\\\"\\u003e5\\u003c/span\\u003e]\\u003c/sup\\u003e. This trend mirrors the epidemic pattern observed in Fujian Province. In 2020, the incidence of varicella in Fujian Province decreased markedly, primarily due to stringent control measures implemented during the COVID-19 pandemic, which led many schools to close or transition to online learning. Following 2021, the incidence of varicella exhibited a slight continuous decline, but began to rise again in 2024. Notably, even during the COVID-19 pandemic, the number of varicella-related outbreaks and cases remained relatively high. A total of 94 varicella outbreaks were reported in Fujian from 2019 to 2024, involving 461 cases, all of which occurred in schools. Varicella cases predominantly affected individuals aged 0\\u0026ndash;17 years, accounting for over 90% of total cases in Fujian Province, with a notable trend toward older age groups in recent years. For instance, the incidence in the 15\\u0026ndash;19 age group in 2024 was significantly higher than in previous years, reaching 193.0 per 100,000. The prevalence of varicella is associated with various factors, including climate models, geographical locations, population density, exposure risks, and other potential influences\\u003csup\\u003e[\\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e]\\u003c/sup\\u003e. To investigate the underlying causes of the high incidence of varicella among children and adolescents in Fujian Province, we analyzed changes in varicella vaccination rates and antibody levels among healthy individuals aged 0\\u0026ndash;17 years. This analysis aims to provide foundational data to support the introduction of the varicella vaccine into the national immunization program.\\u003c/p\\u003e \\u003cp\\u003eAccording to our survey results, the seroprevalence and GMC of IgG antibodies against Varicella-Zoster Virus (VZV) in children aged 0\\u0026ndash;17 years in Fujian Province in 2023 were low, with values of only 47.7% and 81.3 mIU/mL, respectively. These figures are comparable to the results from Jiangsu Province in 2016, which reported a seroprevalence of 43.5%\\u003csup\\u003e[\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e]\\u003c/sup\\u003e. However, they are significantly lower than those reported in Hangzhou City in 2018 (65.59%) \\u003csup\\u003e[\\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e]\\u003c/sup\\u003e and in Beijing in 2012 (84.5%)\\u003csup\\u003e[\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e]\\u003c/sup\\u003e. This discrepancy may be attributed to the low coverage rate of the varicella vaccine in Fujian Province. Specifically, the coverage rate for individuals aged 1\\u0026ndash;17 years who received single dose of the varicella vaccine was 54.9%, while the rate for those receiving two doses was only 17.4%. These figures are markedly lower than those from a 2017 survey in Japan, which indicated a one-dose coverage rate of 67.0% among primary school students, with a two-dose coverage rate of 31.0%\\u003csup\\u003e[\\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e]\\u003c/sup\\u003e, which significantly less than the 80% threshold recommended by the WHO to achieve herd immunity\\u003csup\\u003e[\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e]\\u003c/sup\\u003e. In contrast, in Italy, a study assessing vaccination coverage in the 2019 birth cohort found that 92.08% of children were vaccinated by 24 months of age in 2021, largely due to mandatory vaccination policies\\u003csup\\u003e[\\u003cspan citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e]\\u003c/sup\\u003e. Furthermore, several domestic cities, including Shanghai, Tianjin, and Suzhou, have incorporated the varicella vaccine into their local Expanded Program on Immunization (EPI) and are providing free vaccinations for children. The findings suggest that a higher vaccination rate correlates with improved protective effects for children \\u003csup\\u003e[\\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e]\\u003c/sup\\u003e.\\u003c/p\\u003e \\u003cp\\u003eSignificant statistical differences in seroprevalence and GMC were observed across different age groups. Children under one year old exhibited the lowest seropositive rate at 12.7%, with a GMC of 33.0 mIU/mL. These findings are consistent with research conducted in other provinces of China \\u003csup\\u003e[\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e],\\u003c/sup\\u003e potentially attributable to the gradual decline of maternal antibodies in this demographic and the timing of varicella vaccination\\u003csup\\u003e[\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e]\\u003c/sup\\u003e. As children age, those over one year old began receiving the varicella vaccine. Our survey indicated that 82.4% of individuals in Fujian Province who were willing to receive the varicella vaccine were vaccinated between the ages of one and two years. Consequently, the seropositive rate and GMC increased significantly to 49.5% and 86.6 mIU/mL, respectively, in children aged two years. Approximately 30% of children vaccinated between the ages of three and four years received a second dose of the vaccine, resulting in an increase in seroprevalence and GMC among children aged three to five years. However, the low coverage of the second dose among school-aged children (17.4%) contributed to relatively minor fluctuations in seroprevalence and GMC within this population, with seroprevalence among individuals aged four to eleven years remaining between 43.9% and 53.6%. The GMC ranged from 91.8 mIU/mL to 115.4 mIU/mL. The persistence of low antibody levels is a significant factor contributing to the high incidence of varicella in this group\\u003csup\\u003e[\\u003cspan citationid=\\\"CR5\\\" class=\\\"CitationRef\\\"\\u003e5\\u003c/span\\u003e]\\u003c/sup\\u003e. Nonetheless, substantial statistical differences in seroprevalence and GMC were still evident among individuals with varying vaccination histories, with the number of vaccine doses positively correlating with both seroprevalence and GMC. This aligns with previous studies indicating that countries and provinces that implemented two doses of the varicella vaccine demonstrate enhanced protection compared to those administering a single dose\\u003csup\\u003e[\\u003cspan citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e, \\u003cspan additionalcitationids=\\\"CR16\\\" citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e\\u0026ndash;\\u003cspan citationid=\\\"CR17\\\" class=\\\"CitationRef\\\"\\u003e17\\u003c/span\\u003e]\\u003c/sup\\u003e. In terms of gender, the seroprevalence and GMC of women were found to be higher than those of men. The basis of the sex difference in VZV seropositivity remains unclear and may involve the levels of virus exposure, incidence, or natural infection\\u003csup\\u003e[\\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e]\\u003c/sup\\u003e. Females tend to have stronger innate and adaptive immune responses than males against both infections and vaccines\\u003csup\\u003e[\\u003cspan citationid=\\\"CR18\\\" class=\\\"CitationRef\\\"\\u003e18\\u003c/span\\u003e]\\u003c/sup\\u003e, and males tend to engage in more activities and exhibit poorer health habits. Therefore, it is understandable that men are more susceptible to varicella\\u003csup\\u003e[\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e]\\u003c/sup\\u003e.\\u003c/p\\u003e \\u003cp\\u003eTo investigate the reduction rule of vaccine antibodies, we analyzed the changes in antibody positive rates and GMC over time following vaccination. Antibody levels remained elevated for 1 to 2 years after the initial dose; however, both seroprevalence and GMC began to decline after the second year. By the third year, seroprevalence and GMC had decreased by 33.8% and 43.4%, respectively. Notably, in the two-dose group, seroprevalence and GMC increased rapidly to 96.6% and 441.1 mIU/mL within six months post-vaccination, maintaining high levels for one year. After one year, both values gradually decreased, and by the fourth year, they had declined by 50.5% and 73.2%, respectively. This finding aligns with other reports\\u003csup\\u003e[\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e, \\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e]\\u003c/sup\\u003e. It is important to note that seroprevalence and GMC decreased after one year, regardless of whether the first or second dose was administered. Following the first dose, although the antibody titer was low, the rate of decline was slower. In contrast, after the second dose, the antibody level increased rapidly, with seroprevalence exceeding 95.0%, but both seroprevalence and GMC declined sharply after one year. Therefore, to optimize the protective effect of the varicella vaccine, it is recommended that the varicella vaccine be included in the national immunization program. Furthermore, the timing of the first and second doses should be designed in a reasonable and scientific manner.\\u003c/p\\u003e \\u003cp\\u003eOur study has several limitations. Firstly, the survey is primarily a cross-sectional study rather than a cohort study, which may compromise the accuracy of the results regarding the decay of vaccine antibody levels over different time intervals. Nonetheless, the substantial sample size can still reflect this decay trend. Secondly, the antibody levels induced by the virus may have been underestimated due to the limitations of the ELISA reagents used. However, these limitations do not affect our analysis of the general trend in antibody distribution among younger age groups in Fujian Province, nor do they hinder the identification of the susceptible population.\\u003c/p\\u003e\"},{\"header\":\"Conclusions\",\"content\":\"\\u003cp\\u003eIn conclusion, the current vaccination strategy for varicella in Fujian Province leading to a low seropositivity rate and geometric mean concentration (GMC) of varicella antibodies among children and adolescents, which is inadequate for effectively controlling the varicella epidemic. The vaccination coverage rate for the varicella vaccine is unsatisfactory, particularly with the second dose coverage rate falling below 20.0%. Furthermore, the antibody levels induced by the varicella vaccine decline rapidly in children, failing to provide sufficient protection. It is recommended to include varicella in the national immunization program and to increase the vaccination rate among school-aged children in order to reduce the incidence of varicella among children and adolescents.\\u003c/p\\u003e\"},{\"header\":\"Declarations\",\"content\":\" \\u003cp\\u003e \\u003cstrong\\u003eEthical approval\\u003c/strong\\u003e \\u003cp\\u003eThe survey was conducted by public health agencies as part of their statutory mandate for routine surveillance and was therefore classified as minimal risk research. No confidential information was involved, and the study was exempt from ethical approval by the Medical Ethics Committee of the Fujian Provincial Center for Disease Control and Prevention. Written informed consent was obtained from the parents or guardians of the children prior to enrollment. The study was conducted by the Declaration of Helsinki, national guidelines, and laws.\\u003c/p\\u003e \\u003ch2\\u003eClinical trial number\\u003c/h2\\u003e \\u003cp\\u003enot applicable.\\u003c/p\\u003e \\u003ch2\\u003eConsent for publication\\u003c/h2\\u003e \\u003cp\\u003eNot applicable.\\u003c/p\\u003e \\u003cp\\u003e \\u003cstrong\\u003eCompeting interests\\u003c/strong\\u003e \\u003cp\\u003eThe authors declare no competing interests\\u003c/p\\u003e \\u003ch2\\u003eFunding\\u003c/h2\\u003e \\u003cp\\u003eThe author(s) reported there is no funding associated with the work featured in this article.\\u003c/p\\u003e\\u003ch2\\u003eAuthor Contribution\\u003c/h2\\u003e\\u003cp\\u003eDongjuan Zhang，Xiuhui Yang，Xiaoling Chu conceived and designed the study. Dong Li, Zhifei Chen, Hairong Zhang, Suhan Zhang, Xiuhui Yang, and Mengping Zhang experimental operation and data analysis. Dong Li wrote the paper. All authors read and approved the manuscript.\\u003c/p\\u003e\\u003ch2\\u003eAcknowledgments\\u003c/h2\\u003e \\u003cp\\u003eWe would like to express our deepest gratitude for all the unnamed participants in the study. This work was supported by the Medical Innovation Project of the Fujian Provincial Health Commission (Grant No. 2025CXA024) and by funding from the Phase III clinical trial of the freeze-dried live attenuated varicella vaccine (NZV-7D).\\u003c/p\\u003e\\u003ch2\\u003eData Availability\\u003c/h2\\u003e\\u003cp\\u003eThe datasets generated and/or analyzed during the current study are available from the corresponding author on reasonable request.\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\u003cli\\u003e\\u003cspan\\u003eGershon AA, Breuer J, Cohen JI, Cohrs RJ, Gershon MD, Gilden D, et al. Varicella zoster virus infection. 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Impact of a 2-dose voluntary vaccination strategy on varicella epidemiology in Beijing, 2011\\u0026ndash;2017. vaccine. 2020;38(20):3690\\u0026ndash;6. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1016/j.vaccine.2020.01.087\\u003c/span\\u003e\\u003cspan address=\\\"10.1016/j.vaccine.2020.01.087\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eNardone A, de Ory F, Carton M, Cohen D, van Damme P, Davidkin I, et al. The comparative sero-epidemiology of varicella zoster virus in 11 countries in the European region. vaccine. 2007;25(45):7866\\u0026ndash;72. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1016/j.vaccine.2007.07.036\\u003c/span\\u003e\\u003cspan address=\\\"10.1016/j.vaccine.2007.07.036\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eWidgren K, Persson Berg L, Morner A, Lindquist L, Tegnell A, Giesecke J, et al. Severe chickenpox disease and seroprevalence in Sweden - implications for general vaccination. Int J Infect Dis. 2021;111:92\\u0026ndash;8. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1016/j.ijid.2021.08.012\\u003c/span\\u003e\\u003cspan address=\\\"10.1016/j.ijid.2021.08.012\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e.\\u003c/span\\u003e\\u003c/li\\u003e\\u003c/ol\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":false,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"bmc-infectious-diseases\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"infd\",\"sideBox\":\"Learn more about [BMC Infectious Diseases](http://bmcinfectdis.biomedcentral.com/)\",\"snPcode\":\"\",\"submissionUrl\":\"https://www.editorialmanager.com/infd\",\"title\":\"BMC Infectious Diseases\",\"twitterHandle\":\"#bmcinfectdis\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"BMC Series\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":true},\"keywords\":\"Seroepidemiological, Varicella-zoster virus, GMC, Vaccine\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-9302231/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-9302231/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003ch2\\u003eBackground\\u003c/h2\\u003e \\u003cp\\u003eVaricella continues to pose a significant public health challenge for children and adolescents in China. Although vaccination is available, the disease remains highly prevalent among children in Fujian. This study aimed to evaluate the seroepidemiology of varicella-zoster virus (VZV) and to explore the factors contributing to its high incidence in individuals aged 0\\u0026ndash;17 years.\\u003c/p\\u003e\\u003ch2\\u003eMethods\\u003c/h2\\u003e \\u003cp\\u003eA cross-sectional serosurvey was conducted in 2023. Serum samples from 2,675 eligible individuals were tested for VZV IgG using ELISA. Demographic and vaccination data were collected via questionnaire.\\u003c/p\\u003e\\u003ch2\\u003eResults\\u003c/h2\\u003e \\u003cp\\u003eThe overall seroprevalence of VZV IgG was 47.7% (95% CI: 45.5\\u0026ndash;49.3), with a geometric mean concentration (GMC) of 81.3 mIU/mL (95% CI: 77.0\\u0026ndash;85.9). Significant variations in these immunity markers were observed across age groups, gender, and vaccination status. Notably, varicella vaccination coverage was substantially low: only 54.9% of children aged 1\\u0026ndash;17 years had received one dose, and merely 17.4% were fully vaccinated with two doses. A clear post-vaccination antibody waning pattern was also evident. Both seroprevalence and GMC began to decline one year after vaccination, decreasing by over 50% after four years.\\u003c/p\\u003e\\u003ch2\\u003eConclusions\\u003c/h2\\u003e \\u003cp\\u003eThe low population immunity and inadequate vaccination coverage, particularly for the second dose (\\u0026lt;\\u0026thinsp;20%), combined with substantial antibody waning, explain the persistent high incidence of varicella. Our findings provide strong evidence to support the urgent integration of the varicella vaccine into the national expanded program on immunization (EPI) and underscore the necessity of promoting two-dose vaccination strategies to achieve effective herd immunity and outbreak control.\\u003c/p\\u003e\",\"manuscriptTitle\":\"Low seroprevalence and rapid antibody waning: A population-based seroepidemiological study of varicella zoster virus among children and adolescents in Fujian, China\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2026-05-04 05:47:05\",\"doi\":\"10.21203/rs.3.rs-9302231/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"decision\",\"content\":\"Revision requested\",\"date\":\"2026-04-27T19:32:27+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"225863392006337709388957605320268370979\",\"date\":\"2026-04-25T17:23:43+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2026-04-23T12:49:16+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"47373220761358774868583881077142648636\",\"date\":\"2026-04-23T12:16:51+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2026-04-23T07:28:24+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewerAgreed\",\"content\":\"12945257151163581319075118282804986744\",\"date\":\"2026-04-21T08:21:09+00:00\",\"index\":\"hide\",\"fulltext\":\"\"},{\"type\":\"reviewersInvited\",\"content\":\"\",\"date\":\"2026-04-20T17:17:45+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorAssigned\",\"content\":\"\",\"date\":\"2026-04-20T17:10:38+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorInvited\",\"content\":\"\",\"date\":\"2026-04-09T20:41:34+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"checksComplete\",\"content\":\"\",\"date\":\"2026-04-09T02:32:05+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"submitted\",\"content\":\"BMC Infectious Diseases\",\"date\":\"2026-04-09T02:27:31+00:00\",\"index\":\"\",\"fulltext\":\"\"}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"bmc-infectious-diseases\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"infd\",\"sideBox\":\"Learn more about [BMC Infectious Diseases](http://bmcinfectdis.biomedcentral.com/)\",\"snPcode\":\"\",\"submissionUrl\":\"https://www.editorialmanager.com/infd\",\"title\":\"BMC Infectious Diseases\",\"twitterHandle\":\"#bmcinfectdis\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"BMC Series\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":true}}],\"origin\":\"\",\"ownerIdentity\":\"e63c8f72-2c1d-49a3-986c-5cef46c1b7cc\",\"owner\":[],\"postedDate\":\"May 4th, 2026\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"under-review\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2026-05-09T09:23:29+00:00\",\"versionOfRecord\":[],\"versionCreatedAt\":\"2026-05-04 05:47:05\",\"video\":\"\",\"vorDoi\":\"\",\"vorDoiUrl\":\"\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-9302231\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-9302231\",\"identity\":\"rs-9302231\",\"version\":[\"v1\"]},\"buildId\":\"XKTyCvWXoU3ODBz1xrDgd\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}