南通市外环境禽流感病毒检测结果和相关因素分析

Analysis on detection results and related factors of avian influenza virus in external environment in Nantong City

目的分析2017—2020年南通市外环境禽流感病毒实验室检测结果和相关影响因素,进一步掌握外环境禽流感病毒的型别、分布特点和流行特征,为南通地区人感染禽流感疫情防控提供科学依据。方法收集2017—2020年南通市1112份外环境标本,使用实时荧光定量反转录-聚合酶链反应(real-time fluorescence quantitative reverse transcription-polymerase chain reaction,RT-PCR)法检测禽流感病毒核酸。结果1112份外环境标本中检出A型流感病毒核酸阳性146份,阳性检出率为13.13%,各年份间阳性检出率差异有统计学意义(P<0.01);H9亚型的阳性检出率最高,为8.00%。2017年和2020年不同季度阳性检出率差异有统计学意义(P<0.05),2018年和2019年不同季度阳性检出率差异无统计学意义(P>0.05)。各类型标本的阳性检出率差异有统计学意义(P<0.05),其中宰杀或摆放禽肉案板表面的擦拭标本阳性检出率最高。各类监测点的阳性检出率差异有统计学意义(P<0.01),其中城乡活禽市场的阳性检出率最高。结论南通市外环境禽流感病毒的优势亚型为H9亚型,近3年阳性检出率呈上升趋势需引起重视,应加强城乡活禽市场的监管力度,有效降低人群感染的风险。

Objective To analyzz the laboratory test results of avian influenza virus in the external environment and related influencing factors in Nantong City from 2017 to 2020,further understand the types,distribution characteristics and epidemic characteristics of the avian influenza virus in the external environment,and provide scientific basis for the prevention and control of human infection with avian influenza virus in Nantong City.Methods A total of 1112 external environmental specimens in Nantong City from 2017 to 2020 were collected,and real-time fluorescence quantitative reverse transcription-polymerase chain reaction(RT-PCR)method was used to detect the nucleic acid of avian influenza virus.Results Totally 146 of 1112 external environmental specimens were positive for the nucleic acid of influenza A virus,the positive detection rate was 13.13%,and the difference in the positive detection rate was statistically significant between years(P<0.01).The positive detection rate of H9 was the highest(8.00%).The difference in positive detection rates among different quarters in 2017 and 2020 was statistically significant(P<0.05),and the difference in positive detection rates among different quarters in 2018 and 2019 was not statistically significant(P>0.05).The difference in the positive detection rate among various types of specimens was statistically significant(P<0.05).Among them,the positive detection rate of wipe specimen from slaughter or place poultry chopping board surface was the highest.The difference in the positive detection rate of various monitoring points was statistically significant(P<0.01),and the positive detection rate of live poultry markets in the urban and rural areas was the highest.Conclusion The dominant subtype of the avian influenza virus in external environment in Nantong City is H9,the positive detection rate has been increasing in the past three years,which should attract more attention,and the supervision of live poultry markets in the urban and rural areas should be strengthened to effectively reduce the risk of infection among the population.