云南省一起人感染H7N9禽流感疫情调查分析

Survey of an epidemic of human infection with avian influenza A(H7N9) in Yunnan

目的对2017年6—7月云南省一起人感染H7N9禽流感疫情进行调查分析,为进一步防制人禽流感提供科学依据。方法对患者、密切接触者和活禽市场开展流行病学调查,并采集病例呼吸道标本和外环境标本进行检测分析。结果 2017年6—7月云南省文山壮族苗族自治州文山市共报告人感染H7N9禽流感确诊病例5例,分别为流感样病例监测2例、不明原因肺炎加强监测2例和密切接触者调查1例,其中女性3例、男性2例,中位年龄34(4.5～55)岁,4例病例发病前有活禽市场暴露史;5例病例发病至首诊平均时间为2 d,入院3 d,确诊9 d,抗病毒治疗7 d;对病例采取隔离治疗、密切接触者医学观察、阳性活禽市场休市等综合措施后,疫情得到有效控制。结论医疗机构加强流感样病例监测和不明原因肺炎监测是及时发现人禽流感病例的重要手段。活禽交易市场定期消毒与休市为降低感染率的关键措施。

Objective To understand the epidemiological characteristics of an epidemic of human infection with avian influenza A (H7N9)virus in Yunnan province and provide evidence for the prevention and control of human infection with avian influenza in the future.Methods A field epidemiological survey was conducted among patients and close contacts and in live-poultry markets.The samples collected from the patients and outdoor environment were detected and analyzed. Results During June-July 2017,five confirmed cases of human infection with avian influenza A (H7N9)virus were reported in Wenshan prefecture of Yunnan,including 2 cases detected in influenza like illness sentinel surveillance,2 cases detected in unexplained pneumonia monitoring and 1case detected in close contacts.Three cases were women and 2 cases were men.The median age was 37 years (4.5-55 years).Four cases had the exposures to live poultry before the onset.The average intervals between the onset and the first medical care seeking,diagnosis,admission hospital and antiviral treatment were 2,3,9 and 7d respectively.All the cases were isolated and treated,and all the close contacts received medical observation,positive live poultry markets were closed.The epidemic was under control effectively.Conclusion The monitoring of unexplained pneumonia and influenza sentinel surveillance in medical institutions are the important means for the timely detection of human infection with avian influenza virus.Regular disinfection and closure of live-poultry markets are key measures to reduce the exposure opportunity.