Yuan Jun, Liu Yu-fei, Li Kui-biao, Zhou Jie, Xie Chao-jun, Cai Wen-feng, Pan Jie-yun, Liu Qing-lian, Xiao Xiao-Ling, DI Biao, Liu Jian-ping, Ma Xiao-wei, Liu Yan-hui, Yang Zhi-cong
Guangzhou Center for Disease Control and Prevention, Guangzhou, China.
Zhonghua Liu Xing Bing Xue Za Zhi. 2012 Nov;33(11):1159-62.
We conducted an epidemiologic investigation to determine the source of infection on an avian influenza (H5N1) case who returned from Guangzhou, in Hong Kong.
Data related to epidemiologic investigation, medical observation on close contacts, Syndromic Surveillance on poultry salesmen, emergency monitoring, detection of the samples, source tracing on potential Avian influenza virus (H5, H7, H9) infected people, situation on environment pollution by avian influenza virus in the markets etc. were gathered. The determination of infection source was through comparing the different genes between the case and positive environmental samples.
The infected case witnessed the procedure of how a live duck was killed, in market A in Guangzhou during May 17(th) to 19(th). The case was diagnosed as respiratory tract infection in 2 Third-grade-Class A hospitals in Guangzhou on May 23(th) and 24(th). The diagnosis was made as Avian influenza cases on May 26(th) after going back to Hong Kong. 23 close contacts and 34 markets poultry salesmen did not show any ILI related symptoms. However, 2 poultry salesmen from the markets nearby the place where the Avian influenza case stayed, were detected having positive H9 avian influenza antibody, with the H9 positive rate as 6.06% (2/33). Among the environmental samples in the 2 markets nearby home of the patient, chopping block was found to have carried H5, with positive rate as 9.8% (5/51) while poultry cage was found to carry H9, with the positive rate as 2.0% (1/51). A H5 positive sample was found with clade 2.3.2.1, same to the case, from a chopping block at the market B where the sources of poultry was the same as market A.
The source of infection seemed to come from the markets in Guangzhou, that calling for the strengthening of poultry market management, for avian influenza prevention. History related to contact of poultry should be gathered when a diagnosis of respiratory tract infection was made. Timely sampling and testing should be made to improve the sensitivity of diagnosis.
我们开展了一项流行病学调查，以确定一名从广州返回香港的甲型H5N1禽流感病例的感染源。
收集了与流行病学调查、密切接触者医学观察、家禽销售人员症状监测、应急监测、样本检测、潜在甲型H5、H7、H9禽流感病毒感染人员溯源、市场禽流感病毒环境污染情况等相关的数据。通过比较病例与环境阳性样本的不同基因来确定感染源。
该感染病例于5月17日至19日在广州A市场目睹了一只活鸭被宰杀的过程。该病例于5月23日和24日在广州的两家三甲医院被诊断为呼吸道感染。5月26日返回香港后被诊断为禽流感病例。23名密切接触者和34名家禽销售人员未出现任何流感样疾病相关症状。然而，在禽流感病例停留地附近市场的2名家禽销售人员检测出H9禽流感抗体阳性，H9阳性率为6.06%（2/33）。在患者家中附近的2个市场的环境样本中，砧板检测出携带H5，阳性率为9.8%（5/51），禽笼检测出携带H9，阳性率为2.0%（1/51）。在B市场的一个砧板上发现了与病例相同的2.3.2.1分支的H5阳性样本，该市场的家禽来源与A市场相同。
感染源似乎来自广州的市场，这就要求加强家禽市场管理以预防禽流感。在诊断呼吸道感染时应收集与家禽接触的相关病史。应及时采样和检测以提高诊断的敏感性。
