Seroprevalence rates of Japanese encephalitis virus IgG antibodies among healthy individuals in Huzhou City, Zhejiang Province, 2023‒2024
10.19428/j.cnki.sjpm.2025.250266
- VernacularTitle:2023—2024年浙江省湖州市健康人群乙型脑炎病毒IgG抗体阳性水平
- Author:
Chao ZHANG
1
;
Jianyong SHEN
1
;
Yan LIU
1
;
Xiaoqi LIU
1
;
Liping HAN
1
Author Information
1. Huzhou Center for Disease Control and Prevention, Huzhou, Zhejiang 313000, China
- Publication Type:Journal Article
- Keywords:
epidemic encephalitis B;
vaccination;
IgG antibody;
healthy population;
Japanese B encephalitis vaccine
- From:
Shanghai Journal of Preventive Medicine
2025;37(12):981-984
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo investigate the seroprevalence of Japanese encephalitis virus (JEV) IgG antibodies among the healthy individuals in Huzhou City, Zhejiang Province, so as to provide a scientific basis for the development of prevention and control strategies for Japanese B encephalitis (JE). MethodsA cross-sectional study was conducted from 2023 to 2024. Serum samples were collected from healthy individuals across 12 age groups (<8 months, 8 months‒<2 years, 2‒<4 years, 4‒<6 years, 6‒<8 years, 8‒<10 years, 10‒<15 years, 15‒<20 years, 20‒<30 years, 30‒<40 years, 40‒<50 years, 50‒ years) and tested for JEV IgG antibody to determine positivity rates. ResultsThe overall JEV IgG antibody seroprevalence rate was 57.75 % among the healthy individuals in Huzhou City. The positivity rates for the age groups of <8 months, 8 months‒<2 years, 2‒<4 years, 4‒<6 years, 6‒<8 years, 8‒<10 years, 10‒<15 years, 15‒<20 years, 20‒<30 years, 30‒<40 years, 40‒<50 years, and 50‒ years were 10.14%, 23.76%, 77.31%, 66.88%, 73.87%, 58.33%, 41.67%, 55.06%, 47.00%, 61.00%, 62.00%, and 92.00%, respectively, with a statistically significant difference observed in different age groups (χ2=243.996, P<0.001). Seroprevalence rates also differed significantly between males and females (χ2=9.999, P=0.002). Among subjects vaccinated with 0,1 or 2 doses of live attenuated Japanese encephalitis virus vaccine (JEV-L), the IgG antibody seroprevalence rate was 4.76%, 27.27% and 72.33%, respectively (χ2=108.568, P<0.001). Within the 2 doses group, the IgG antibody seroprevalence rate at <1 year, 1 year, 2 years and 3‒5 years after immunization were 80.85%, 77.36%, 66.67% and 65.45%, respectively, indicating a declining trend with time increased since vaccination (Z=-2.024, P=0.043). ConclusionAdults aged 50‒ years maintain high antibody levels, whereas levels are lower among the age groups of <2 years and 8‒<30 years and wane with time since vaccination in Huzhou City. It is recommended to maintain the routine JE vaccination schedule while exploring booster vaccination strategies for the age groups of 8‒<30 years, in order to enhance population immunity against JEV.