Epidemic characteristics of epidemic Japanese encephalitis and antibody levels in healthy people in Longnan City, Gansu Province from 2015 to 2020
10.3760/cma.j.cn231583-20210226-00050
- VernacularTitle:2015 - 2020年甘肃省陇南市流行性乙型脑炎流行特征及健康人群抗体水平分析
- Author:
Yucheng CAI
1
;
Xiaojun WANG
;
Yuankun ZHAO
;
Yan ZHANG
;
Yanxia WANG
Author Information
1. 甘肃省陇南市疾病预防控制中心传染病预防控制科 746000
- Keywords:
Epidemic Japanese encephalitis;
Epidemic characteristics;
Healthy population;
Antibody
- From:
Chinese Journal of Endemiology
2021;40(12):1011-1016
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To understand the epidemic characteristics of epidemic Japanese encephalitis and the antibody level of healthy people in Longnan City, Gansu Province, analyze and evaluate its epidemic risk, and provide scientific basis for future prevention and control of Japanese encephalitis.Methods:By retrospective analysis, the data of Japanese encephalitis cases in Longnan City from 2015 to 2020 were collected from the "Japanese Encephalitis Monitoring Information Report Management System" of the "China Disease Prevention and Control Information System", and the distributions of the cases(time, region and population distribution) were statistically described and analyzed. In 2018, the cluster stratified sampling method was adopted to select Li County and Xihe County with higher incidence rate of Japanese encephalitis in Longnan City, and Wudu District and Hui County with lower incidence rate as monitoring sites, and 3 administrative villages (communities) were selected from each monitoring site to collect blood samples from healthy people to detect the level of Japanese encephalitis IgG antibodies.Results:From 2015 to 2020, a total of 261 cases of Japanese encephalitis were reported in Longnan City, with an average annual incidence of 1.66 per 100 000; among them, the number of reported cases in 2017 and 2018 accounted for 82.38% (215/261) of the total number of cases. The incidence of Japanese encephalitis was mainly concentrated in August, accounting for 72.03% (188/261); 9 counties (districts) in Longnan City had reported cases of Japanese encephalitis, and the top 5 counties (districts) with the number of cases were Li County (68 cases), Xihe County (64 cases), Wudu District (40 cases), Kang County (33 cases) and Cheng County (18 cases), accounting for 85.44% (223/261) of the total number of cases. The age of onset of Japanese encephalitis cases was mainly concentrated in the 40 - < 60 years old, accounting for 40.23% (105/261); male to female ratio was 1.00 ∶ 1.14 (122 ∶ 139); the occupation was mainly farmers, accounting for 75.86% (198/261). A total of 887 sera samples from healthy people were tested, and the antibody positive rate was 91.09% (808/887); the difference in antibody positive rate of different age groups was statistically significant (χ 2 = 5.77, P < 0.05); the differences of positive rate of antibodies between different genders and regions were not statistically significant (χ 2 = 0.45, 2.06, P > 0.05). Conclusions:The incidence of Japanese encephalitis in Longnan City is mainly middle-aged farmers, with a high incidence in August each year. After the outbreak of Japanese encephalitis in Longnan City in 2017 and 2018, it has showed a low epidemic trend, and the positive rate of Japanese encephalitis antibody in healthy people is high. It is recommended to carry out regular monitoring of Japanese encephalitis immunization level of healthy people and strengthen the immunization of key populations in time.
