Avian influenza virus surveillance in the poultry market environment in Zhaoqing, Guangdong, 2015-2018

Abstract

Objective To understand the dynamic distribution of avian influenza virus in poultry market environment in Zhaoqing from 2015 to 2018, and we provide reference for early warning and prevention and control of avian influenza in Zhaoqing.

Methods Environmental specimens were collected from 9 counties(cities and districts) in Zhaoqing from 2015 to 2018. The nucleic acid of influenza A virus (FluA) was detected by real-time PCR. The FluA positive specimens were classified into H5, H7 and H9 subtypes of influenza virus.

Results A total of 4 508 environmental specimens were collected in the poultry markets, of which 1 154 were FluA nucleic acid-positive specimens, and the total positive detection rate was 25.60%; The positive detection rates of H5, H7, H9 and undifferentiated type A were 5.72%, 2.75%, 17.48% and 4.44% respectively. The difference of FluA positive detection rate in 9 counties (city, district) of Zhaoqing had statistical significance ( P<0.05), of which the highest positive detection rate was in Dinghu District . FluA and other subtypes positive detection rates were significantly higher in January and February than other months, winter and spring were the peak seasons for avian influenza epidemic. FluA positive detection rate was significantly different among 5 types of specimens ( P<0.05). Among them, the positive rate of wiping specimens on the surface of the cutting board (referred to as chopping board) was the highest (33.04%), followed by the wiping specimens on the surface of the cage(referred to as cage)(27.22%).

Conclusion There are potential transmission risks of H5, H7, H9 and various subtypes of pathogenic avian influenza virus in the poultry market environment of Zhaoqing, especially in winter and spring. Combined with the prevalence of highly pathogenic avian influenza in humans, it is necessary to strengthen the health education of poultry workers and the surveillance of avian influenza virus in poultry market environment, which is of great significance for the early warning and risk assessment of human infection with avian influenza.

Abstract

摘要： 目的 了解肇庆市 2015—2018 年禽类市场环境中禽流感病毒的动态分布情况, 为肇庆市禽流感预警和防控 工作提供参考依据。 方法 采集 2015—2018 年肇庆市 9 个县 (市、区) 的禽类市场环境标本, 用实时荧光 PCR 法进行 A 型流感病毒(FluA)核酸检测, FluA 阳性标本进行 H5、H7、H9 亚型流感病毒分型。 结果 共采集禽类市场环境标本 4 508 份, 其中 FluA 核酸阳性标本共 1 154 份, 总阳性检出率为 25.60%; H5、H7、H9 和 A 型未分型阳性检出率分别为 5.72%、2.75%、17.48% 和 4.44%。FluA 阳性检出率在肇庆市 9 个县 (市、区) 之间差异有统计学意义( P<0.05), 其中阳性检 出率最高是鼎湖区。FluA 阳性检出率及其他亚型阳性检出率在 1、2 月份明显高于其他月份, 冬春季为禽流感病毒的感 染高峰期。FluA 阳性检出率在 5 种类型监测标本之间差异具有统计学意义( P<0.05), 其中宰杀或摆放禽肉案板表面的 擦拭标本(简称案板)阳性检出率最高(33.04%), 笼具表面擦拭标本(简称笼具)次之(27.22%)。 结论 肇庆市禽类市场环 境中存在 H5、H7、H9 及多种亚型混合的致病性禽流感病毒潜在传播风险, 尤其在冬春季, 需结合人感染高致病性禽流 感的流行状况, 加强禽类从业人群的健康教育与禽类市场环境禽流感病毒监测, 对人感染禽流感发生的预警和风险评 估有重要意义。