2013年云浮市外环境禽流感病毒分布监测分析

Surveillance analysis on the environment of avian influenza in Yunfu,2013

目的了解云浮市禽类规模养殖场和活禽市场外环境中禽流感病毒的分布情况,为防控人感染高致病性禽流感提供科学依据。方法在监测点内采集相应的外环境标本,采用荧光定量PCR方法检测Flu A、H5、H7和H9病毒核酸。结果 2013年全年共采集有效标本234份,A型阳性42份,总阳性率为18.0%(42/234);其中A(H5)5份(11.9%),A(H9)22份(52.4%),未分型15份(35.7%),A(H7)未检出。234份有效标本中,来自家禽规模养殖场107份,未检出A型阳性;来自城乡活禽市场127份,A型阳性42份,阳性率为33.1%(42/127),两类监测点标本阳性率的差异有统计学意义(χ2=43.1,P<0.01)。除禽类饮水标本外,5种类型标本(宰杀或摆放禽肉案板表面的擦拭标本、笼具表面擦拭物、清洗禽类的污水、粪便)阳性率差异有统计学意义(χ2=7.85,P<0.05)。有采样的月份均可检出A型阳性,一、三、四季度阳性检出率相当,二季度最低。结论云浮市外环境存在禽流感病毒污染,H9亚型是主要的病原体,同时存在H5和其他亚型禽流感病毒污染,活禽市场是人感染高致病性禽流感的高风险场所。

Objective To analyze the avian influenza status of Yunfu,and provide scientific bases for the prevention and control of human infection with highly pathogenic avian influenza. Method The environmental samples were tested for Flu A A（H5）, A（H7） and A（H9） subtypes by RT-PCR. Results A total of 234 specimens were collected in 2013 with a positive rate of 18.0%（42 / 234）. Of 42 positive specimens,5 were A（H5）,22 were A（H9）,15 were other subtypes.No A（H7）was detected. Of 234 valid specimens,107 from poultry farm were not detected in influenza A,127 from urban and rural live poultry market were detected in influenza A with a positive rate of 33.1%（42 / 127）. The difference of positive rate of two kind of surveillance points was statistically significant（χ2=43.1,P 〈0.01）. In addition to poultry drinking water specimens, the difference of the positive rate of the four types of specimens（placing poultry board surface swab,cage surface swab,cleaning poultry wastewater,feces）were statistically significant（χ2=7.85,P 〈0.05）. Influenza A could be detected in the months of sampling. Difference of positive rate in the first,third and fourth quarter was not big,the second quarter was the lowest. Conclusions The environment has been contaminated with avian influenza virus. A（H9） was the prevailing subtype. There were A（H5） and other subtypes,also.Urban and rural live poultry markets were high risk places of human infection with highly pathogenic avian influenza.