黄山市首例人感染H7N9禽流感病例流行病学调查

Epidemiologic Investigation of the First Human Infection with H7N9 avian influenza virus in Huangshan City

目的通过对人感染H7N9禽流感病例的流行病学调查,为进一步防控提供科学依据。方法运用描述流行病学方法对患者、密切接触者、患者暴露的农贸市场和周边活禽销售、批发市场开展现场流行病学调查,采集市场外环境标本进行检测分析,进行疑似病例排查和流感样病例强化监测。结果患者有禽类接触史,下呼吸道标本禽流感病毒H7N9核酸阳性。密切接触者中无不明原因肺炎病例,未发现人与人之间传播证据,农贸市场、批发市场环境标本H7N9禽流感病毒核酸检测阳性率分别为44.4%、29.4%。结论黄山市首例人感染高致病性禽流感病例属本地感染、非人传人的病例,感染来源可能与农贸市场环境暴露有关。

Objective To investigate epidemiological characteristic of the first human infection case of H7N9 virus so as to provide scientific evidence for further prevention and control of the disease. Methods The patient and his close contacts,community farmers＇ markets,and the surrounding live poultry sales and wholesale markets were field- investigated in descriptive epidemiological way. The markets＇ environmental specimens were collected for detection. And the screening of suspected cases and monitoring of influenza- like cases were also strengthened at the same time. Results The patient had a clear history of contact with poultry and nucleic acids of H7N9 avian influenza virus was detected from his low respiratory specimens. No unknown pneumonia case was detected among the close contacts. No evidence of human- to- human transmission was found. And the positive rates of nucleic acids of H7N9 avian influenza virus of environmental specimens were44. 4% in community farmers＇ markets and 29. 4% in wholesale markets respectively. Conlusions The first human infection ease with H7N9 avian influenza virus in Huangshan city was a local non- human- to- human transmitted infection.The origin of infection might be related to the environmental exposure to the community farmers＇ markets.