泰州市人感染H7N9禽流感疫情及相关因素分析

目的 了解2015—2018年近四年来泰州市人感染禽流感疫情的流行病学特征,为今后防控人感染禽流感提供参考。 方法 以近四年来泰州市人感染H7N9禽流感疫情及禽、环境监测数据为基础,分析禽流感疫情与禽、环境病毒分布的关系。 结果 研究期间泰州市共报告人感染H7N9禽流感18例,发病日期分布于2016年12月—2017年3月。禽、环境监测样本1 488份,发现阳性120份,其中H7N9病毒核酸阳性32份。疫情由南向北、呈现以人口密集区域为中心向周边扩散的趋势。 统计学分析病例数与禽、环境监测H7N9标本阳性率相关性未显示统计学意义(r=0.738,P>0.05)。病例咽拭子H7N9禽流感核酸检测阳性,在病例暴露的活禽交易场所环境样本中检出H7N9禽流感病毒核酸阳性,121名密切接触者核酸检测阴性。 结论 疫情冬春季节高发,禽、环境监测H7N9病毒核酸阳性的地区更易出现疫情,活禽交易可能是疫情传播与扩散的主要途径,疫情与禽、环境阳性监测结果趋势一致。

Epidemic situation of human infection with avian influenza A H7N9 virus and its related factors in Taizhou city

Objective To investigate the epidemiological characteristics of human infection with avian influenza A H7 N9 virus in Taizhou city in 2015-2018,and to provide a basis for its prevention and control in future.Methods Based on the cases of human infection with avian influenza A H7 N9 virus and the monitoring data of poultry and environment in Taizhou city from 2015 to 2018,the relationship between the epidemic situation of avian influenza and the distribution of poultry and environment viruses was analyzed.Results A total of 18 cases of human infection with avian influenza A H7 N9 virus were reported in Taizhou city during 2015-2018,and the onset dates were from December 2016 to March 2017.Out of the 1,488 poultry and environment samples,120 were found to be positive for avian influenza virus,and H7 N9 virus nucleic acid was detected in 32 samples.The epidemics spread from south to north and showed a tendency from densely populated areas to surrounding areas.No statistically significant difference was observed in the correlation between the number of the cases and the positive rate of H7 N9 virus in the monitoring samples collected from poultry and environment(r=0.738,P>0.05).The pharyngeal swabs of all cases showed positive in H7 N9 avian influenza virus nucleic acid test.H7 N9 avian influenza virus nucleic acid was detected in the environmental samples collected from live poultry markets where the cases were exposed to,but was not detected in 121 close contacts.Conclusions Human infections with avian influenza A(H7 N9)virus occur highly in winter and spring,and the outbreaks are more likely to occur in areas with positive H7 N9 avian influenza virus nucleic acid detection in poultry and environment monitoring.Live poultry trading may be the main way to spread the epidemic.The epidemic situation is consistent with the trends from poultry and environment monitoring results.