陕西省榆林市某县规模鸡场H7亚型流感血清学调查与风险因素分析

Serological Investigation and Risk Factor Analysis of H7 Subtype Influenza in Large-scale Chicken Farms in One County of Yulin City,Shaanxi Province

为了解H7亚型流感在规模鸡场的血清学流行率、分布情况和风险因素,2017年4—5月,以陕西省榆林市某县存栏大于500羽的267个规模鸡场为研究对象,采取两阶段抽样方法,对该县144个规模场开展了血清学检测和问卷调查。结果显示:该县规模鸡场H7亚型流感表观流行率(HPA)为13.89%(95%CI:8.69%～20.63%);阳性区域相对集中,20个血清学阳性场中,有11个分布在2个镇。单因素分析显示:"本场人员到过其他禽场""有外来车辆进入本场"2个因素具有统计学意义。针对上述2个风险因素,建立的多因素回归分析模型的拟合度较好,ROC曲线下面积为0.714(95%CI:0.585～0.843)。结果提示,规模鸡场要严格控制场间的人员流动,外来车辆进入本场时要做好消毒。

In order to investigate the prevalence, distribution situation and risk factors of H7 subtype influenza in large-scale chicken farms, during May to June of 2017, 267 farms (raising more than 500 chickens) in one county in Yulin City of Shaanxi Province were taken as the research targets. Adopting two-stage sampling method, serological tests and questionnaire surveys were carried out towards 144 such farms. The results revealed that the apparent prevalence (HPA) of H7 subtype influenza was 13.89%(95%CI:8.69% to 20.63%). Spatial distribution map showed 20 positive farms were mainly concentrated in two towns. According to single factor analysis, two possible risk factors were found, which were "there were people who had been to other poultry farms" and "there were foreign vehicles entering the farm" . Aim at this, a multi-factor regression model was established and its fitting degree was reasonable. The area under the ROC curve was 0.714 (95%CI: 0.585 to 0.843) . Based on the results, it was indicated that personnel movement between different farms should be strictly controlled, and the foreign vehicles should be disinfected when entering the farm.