甘肃省白银市职业暴露人群及外环境高致病性禽流感监测分析

Analysis of surveillance of highly pathogenic avian influenza in occupational exposure crowd and environment in Baiyin City

目的了解甘肃省白银市禽流感职业暴露人群感染情况及外环境禽流感病毒H5、H7和H9亚型污染状况,为人禽流感防控提供科学依据。方法选择禽类养殖业较为发达地区作为监测场所,采集职业暴露人群血清标本以及外环境标本,利用马红细胞血凝抑制实验(HI)检测血清标本H5、H7禽流感抗体,对外环境标本进行禽流感病毒核酸检测。结果 290份外环境标本中禽流感病毒核酸检测阳性49份,阳性率为16.90%,其中H9阳性48份,H7可疑阳性1份;不同时间(χ2=21.655)和不同类型标本(χ2=16.934)阳性率差异有统计学意义(均P<0.05),不同监测场所阳性率差异无统计学意义(χ2=1.203,P>0.05);200份职业暴露人群血清H5、H7血凝素抗体检测均为阴性。结论白银市职业暴露人群尚未发现高致病禽流感病毒隐性感染,外环境中H9亚型禽流感病毒普遍存在,城乡活禽市场和家禽规模养殖厂均是禽流感病毒的集散地;健全活禽交易市场和农贸市场检疫制度的同时,还应加强禽类养殖场的防疫工作。

Objective To learn the infection of avian influenza in occupational exposure crowd and pollution situation of avian influenza virus H5,H7, and H9 subtypes in external environment, to provide a scientific basis for avian influenza pre- vention. Methods Regions with developed poultry industry were selected as the monitoring sites, and environmental sam- ples and serological samples of occupationally exposed populations were collected and detected. The serum samples were de- tected for H5, H7 avian influenza antibodies with horse blood serum samples inhibition （HI） and the external environment samples were detected with avian flu virus nucleic acid method. Results Out of the 290 external environment specimens, 49 specimens were positive of avian influenza viral nucleic acid with positive rate of 16.90%, including 48 specimens of H9 positive and 1 specimen of H7 probable positive. There was statistical difference （P〈0.05） in positive rate between various time （χ2=21.655） and various samples （χ2=16.934）, and no statistical difference in positive rate among monitoring sites （χ2= 1.203, P〉0.05）. H5 and H7 antibodies of 200 sera of occupationally exposed crowd were negative. Conclusions There is no case subclinically infected with avian influenza in the exposure crowds in Baiyin City, but avian influenza virus H9 sub- type is widespread in external environment. Avian influenza virus exists in transshipment center such as poultry sales market and poultry farms. Quarantine system for poultry trading market should be improved and epidemic prevention in poultry farms should be strengthened.