Adults in Northwest China experienced the largest outbreak of Japanese encephalitis in history 10 years after the Japanese encephalitis vaccine was included in the national immunization program: A retrospective epidemiological study.
J Med Virol
; 95(5): e28782, 2023 05.
Article
em En
| MEDLINE
| ID: mdl-37212323
ABSTRACT
Mainland China included Japanese encephalitis (JE) vaccine in the national immunization program in 2008 to control the JE epidemic. However, Gansu province in Western China experienced the largest JE outbreak since 1958 in 2018. We conducted a retrospective epidemiological study to explore the causes of this outbreak. We found that adults aged ≥20 years (especially those in rural areas) were the main JE cases in Gansu Province, with a significant increase in the JE incidence in older adults aged ≥60 years in 2017 and 2018. In addition, JE outbreaks in Gansu Province were mainly located in the southeastern region, while the temperature and precipitation in Gansu Province were gradually increasing in recent years, which made the JE epidemic areas in Gansu Province gradually spread to the western of Gansu Province. We also found that adults aged ≥20 years in Gansu Province had lower JE antibody positivity than children and infants, and the antibody positivity rate decreased with age. In the summer of 2017 and 2018, the density of mosquitoes (mainly the Culex tritaeniorhynchus) in Gansu Province was significantly higher than in other years, and the genotype of JEV was mainly Genotype-G1. Therefore, in the future JE control in Gansu Province, we need to strengthen JE vaccination for adults. Moreover, strengthening mosquito surveillance can provide early warning of JE outbreaks and the spread of epidemic areas in Gansu Province. At the same time, strengthening JE antibody surveillance is also necessary for JE control.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Encefalite Japonesa
/
Vacinas contra Encefalite Japonesa
/
Vírus da Encefalite Japonesa (Espécie)
/
Culicidae
Tipo de estudo:
Observational_studies
/
Risk_factors_studies
Limite:
Aged
/
Animals
/
Child
/
Humans
/
Infant
País/Região como assunto:
Asia
Idioma:
En
Revista:
J Med Virol
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
China