2020-2023年山东省涉禽外环境禽流感病毒监测分析

Monitoring and analysis of avian influenza virus in poultry related environments in Shandong Province from 2020 to 2023

目的了解山东省涉禽场所外环境中禽流感病毒的污染情况,为人感染禽流感疫情的防控提供科学依据。方法2020-2023年从山东省16个地市4类涉禽场所采集外环境样本,使用实时荧光定量PCR法进行A型流感病毒核酸检测,阳性样本再进行H5、H7和H9亚型禽流感病毒的核酸分型,描述山东省涉禽外环境中禽流感病毒的流行病学特征,率间比较采用χ^(2)检验进行结果分析。结果2020-2023年,山东省涉禽场所共采集外环境标本6523份,检出禽流感病毒阳性1007份,阳性率为15.44%。H5、H7和H9亚型及混合感染均有检出,阳性标本中以H9亚型为主(88.48%)。不同地市阳性率差异较大(χ^(2)=431.956,P<0.001),其中阳性率最高的地市达28.93%。不同监测场所(χ^(2)=304.604,P<0.001)、不同类型样本(χ^(2)=109.678,P<0.001)、不同季度(χ^(2)=64.963,P<0.001)阳性率差异有统计学意义。其中,监测场所以城乡活禽市场阳性检出率(20.12%)最高,样本类型中宰杀或摆放禽肉案板表面擦拭标本阳性检出率(22.56%)高于其他样本,阳性检出率最高峰出现在春季(20.31%)。结论山东省涉禽外环境中普遍存在禽流感病毒污染,H9亚型为主要病原体,H5、H7亚型共流行,存在人感染禽流感的风险,应加强重点季节、重点地区、重点场所、重点环节的禽流感防控工作。

This study was aimed at understanding the pollution distribution pattern of avian influenza virus in the environment in poultry related places in Shandong Province,to provide a scientific basis for the prevention,control,prediction,and early warning regarding human infection with avian influenza.From 2020 to 2023,6523 environmental samples were collected in 16 cities in Shandong Province from four types of poultry-related places.Fluorescence quantitative PCR was used for nucleic acid testing of influenza A virus.Positive samples were further identified for the H5,H7,and H9 subtypes of avian influenza virus.The epidemiological characteristics of avian influenza viruses in the poultry related environment of Shandong Province were described,and inter-rate comparisons were performed with the χ^(2) test.During 2020-2023,6523 environmental samples were collected,and 1007 cases positive for avian influenza virus were detected,with a positivity rate of 15.44%.H5,H7,and H9 subtypes and mixed infections were detected.H9 was the main subtype(88.48%)in positive specimens.A significant difference in positivity rates was observed among regions(χ^(2)=431.956,P<0.001),and the highest positivity rate was 28.93%.Significant differences in positivity rates were observed among monitoring sites(χ^(2)=304.604,P<0.001),sample types(χ^(2)=109.678,P<0.001),and quarters(χ^(2)=64.963,P<0.001).The positive detection rate was highest at monitoring sites in urban and rural live poultry markets(20.12%),and the positive detection rate of samples collected by wiping meat cutting board surfaces was higher than that of other samples(22.56%).The peak positive detection rate occurred in spring(20.31%).Widespread contamination with avian influenza virus was observed in poultry environments in Shandong Province.The H9 subtype,the main pathogen,coexisted with H5 and H7 subtypes,thus posing a risk of human infection with avian influenza.Therefore,prevention and control of avian influenza must be strengthened in key seasons,areas,places,and links.