广州市活禽批发市场活禽流感感染风险因素调查

Risk Factor Survey on Live Poultry Infection with Influenza Virus in Live Poultry Wholesale Markets in Guangzhou City

为探究活禽进入广州市活禽批发市场前后的流感感染率动态变化及相关风险因素,从而为科学防控人感染H7N9流感提供依据,2017年4月,选择广州市2个活禽批发市场,于进场时和进场后24 h两个时间点,分别采集活禽口咽/泄殖腔棉拭子990份,采用荧光RT-PCR方法检测通用型流感病毒,同时以问卷方式,对有关流感传播风险因素进行调查。结果显示:2个活禽批发市场进场前后的活禽通用型流感病毒阳性率分别为24.24%和53.79%,活鸡、来自外省的活禽、档口清洗消毒频次小于1次/周等因素是活禽批发市场活禽感染流感的主要风险因素;Logistic回归拟合度较好(P>0.05),ROC曲线下面积为0.659(95%CI:0.618~0.700)。结果表明:活禽从养殖场进入批发市场24 h后,通用型流感病毒阳性率明显上升,说明活禽市场助推了病毒的散播;外省活禽感染率高于本地活禽,提示应加强对外省活禽的流感监测;活禽档口的存栏密度及清洗消毒频次与活禽流感感染相关,因而应保持经营档口适当的活禽密度,并严格落实清洗消毒措施。

In order to recognize the dynamic changes of influenza infection rate and relevant risk factors before and after the live birds entering into the live poultry wholesale markets(LBMs)in Guangzhou City,and to provide the basis for scientific prevention and control of human infection of H7N9 influenza,two markets were selected in April 2017,and then 990 oral/cloacal swab samples were collected at the moment before and after(24 hours)the poultry entering into LBMs. The samples were tested for general AIV by fluorescence RT-PCR. Questionnaires were carried out at the same time to investigate the risk factors for the spread of influenza. The results showed that the average prevalence in two markets before and after the poultry entering into LBMs were 24.24% and 53.79%,respectively. The main risk factors included live chicken,the poultry from other provinces and cleaning and disinfection frequency of less than once per week. The fitting degree of logistic regression was good(P>0.05),and the area under ROC curve was 0.659(95%CI :0.618 to 0.700). The results indicated that the general Influenza virus positive rate increased significantly after 24-hour staying of poultry in LBMs,which proved that the live poultry markets boosted the spread of the virus. The prevalence rate in poultry from other provinces was higher than that in local live poultry,indicating the inspection and quarantine towards live poultry from other provinces should be strengthened. The density of live poultry in stalls and the cleaning and disinfection frequency were associated with influenza virus infection,hence proper raising density should be maintained and strict cleaning and disinfection measures should be implemented.