深圳市活禽市场活禽经营人员H7N9禽流感病毒抗体水平及感染危险因素调查

目的调查深圳市活禽市场活禽经营人员H7N9禽流感病毒抗体水平,探讨感染危险因素。方法在对活禽市场活禽经营人员问卷调查的基础上,采集血样,用血凝抑制试验检测H7N9禽流感病毒抗体,采用单因素分析和多因素logistic回归对H7N9病毒感染的危险因素进行分析。结果250名活禽市场活禽经营中,男性141人,女性109人,年龄中位数为41岁, 38人（15.2%）H7N9病毒抗体阳性（滴度≥1：160）,男、女各19人。问卷调查发现,236人（94.4%）主要接触鸡,169人（67.6%）接触过鸭,120人（48.0%）接触过鹅,105人（34.1%）接触过鸽子,单因素分析显示接触鸭子、鹅和鸽子为H7N9病毒感染的高危因素,进一步多因素logistic回归分析结果显示,接触鸭子为H7N9病毒感染的高危因素（OR=3.85,95%CI：1.44-10.35,P=0.007）,活禽暴露时间,暴露方式和流感疫苗接种等因素对H7N9病毒感染的影响没有显著性(P>0.05)。结论活禽市场活禽经营人员中存在这一定数量的隐性感染者,接触鸭子为H7N9病毒感染的危险因素 。

A study on the seroprevalence to H7N9 avian influenza virus among poultry workers and risk factors for H7N9 infection in Shenzhen

ObjectiveWe aimed to examine the seroprevalence to H7N9 virus among poultry workers in Shenzhen and identify related risk factors.MethodsSubjects were recruited in poultry markets, and questionnaire was administered. Blood samples were taken for detecting antibody to novel influenza A H7N9 virus by using hemagglutination-inhibition test. Multivariate analysis was employed to identify risk factors related to H7N9 infection.Results250 subjects were recruited for serological survey with age median of 41,including 141 males and 109 females. 38 (15.2%) poultry workers had HI antibody titer≥1:160 to novel influenza A H7N9 virus, including 19 males and 19 females. Investigation showed that 236（94.4%）had exposure to chicken, 169（67.6%）had exposure to duck, 120（48.0%）had exposure to goose, 105（34.1%）had exposure to pigeon. In the univariate analysis, exposure to duck, goose and pigeon were identified as risk factors for H7N9 infection. In the multivariate analysis, exposure to duck(OR 3.85, 95%CI（1.44-10.35）, P=0.007)was identified as a risk factor for H7N9 virus infection, and other factors such as length of exposure to poultry, way of exposure and seasonal influenza vaccination were not identified to affect H7N9 infection significantly. ConclusionsThe comparatively high seropositivity to novel influenza A H7N9 virus among poultry workers in Shenzhen suggests that there are asymptomatic patientsin them.Exposure to duck is a risk factor for H7N9 virus infection.