目的:确定2022年爆发期间新南威尔士州城镇中日本脑炎病毒(JEV)感染高危人群的比例;确定JEV感染的危险因素。
方法:新南威尔士州JEV特异性抗体血清阳性率的横断面血清调查研究。
方法:在2022年初澳大利亚东南部首次爆发日本脑炎后,来自新南威尔士州五个地区城镇的人群(所有年龄段)的便利样本(Balranald,Corowa,Dubbo,格里菲斯,Temora),2022年6月21日-7月22日。
方法:JEV总抗体血清阳性的人群比例,通过确定的表位阻断酶联免疫吸附试验进行分析;暴露风险因素和保护行为的患病率比值比。
结果:917名合格参与者中有80名(559名女孩或妇女,61%;42名原住民和托雷斯海峡岛民,4.6%;中位年龄,52年[IQR,37-62岁])的JEV特异性总抗体呈血清阳性(8.7%);血清阳性人群的中位年龄为61岁(IQR,48-70岁)。65岁或以上人群的血清阳性比例最大(192人中有30人;加权比例,13.7%),男性参与者大于女性参与者(358人中的30人,10.6%v559人中的50人,7.5%)。来自原住民和托雷斯海峡岛民的42个样本中有5个呈血清阳性(12%)。我们发现与一系列潜在风险因素的混合关联。
结论:我们在2022年的一个虫媒病毒季节中发现了新南威尔士州五个地区城镇中大量JEV感染的证据。公共卫生对策,包括有效的监视,针对JEV的疫苗接种,和蚊子管理,对控制疫情至关重要。促进减少蚊子接触的行为是预防的核心组成部分,特别是当疫苗供应有限时。
OBJECTIVE: To determine the proportion of people in New South Wales towns at high risk of Japanese encephalitis virus (JEV) infections during the 2022 outbreak; to identify risk factors for JEV infection.
METHODS: Cross-sectional serosurvey study of the seroprevalence of JEV-specific antibodies in NSW.
METHODS: Convenience sample of people (all ages) from five regional NSW towns deemed to be at high risk of JEV infections after first outbreak of Japanese encephalitis in southeastern Australia in early 2022 (Balranald, Corowa, Dubbo, Griffith, Temora), 21 June - 22 July 2022.
METHODS: Proportion of people seropositive for JEV total antibody, assayed by defined epitope-blocking enzyme-linked immunosorbent assay; prevalence odds ratios for exposure risk factors and protective behaviours.
RESULTS: Eighty of 917 eligible participants (559 girls or women, 61%; 42 Aboriginal and Torres Strait Islander people, 4.6%; median age, 52 years [IQR, 37-62 years]) were seropositive for JEV-specific total antibody (8.7%); the median age of seropositive people was 61 years (IQR, 48-70 years). The seropositivity proportion was largest for people aged 65 years or more (30 of 192; weighted proportion, 13.7%) and larger for male than female participants (30 of 358, 10.6% v 50 of 559, 7.5%). Five of 42 samples from Aboriginal and Torres Strait Islander participants were seropositive (12%). We found mixed associations with a range of potential risk factors.
CONCLUSIONS: We found evidence for a substantial number of JEV infections in five regional NSW towns during a single arbovirus season in 2022. Public health responses, including effective surveillance, vaccination against JEV, and mosquito management, are critical for controlling outbreaks. Promoting behaviours that reduce exposure to mosquitoes is a core component of prevention, particularly when the vaccine supply is limited.