深圳市龙岗区活禽市场外环境流感病毒污染监测及休市措施效果评价

Monitoring on contamination of external environment of live poultry markets by avian influenza virus and effect evaluation on closure of live poultry markets in Longgang District

目的通过对活禽市场外环境监测,评估不同管理措施对控制禽流感病毒污染的效果。方法 2014年12月-2015年2月,在深圳市统一休市前后,采集龙岗区8个街道16个活禽市场的外环境标本,采用RT-PCR法进行A型、H5亚型、H9亚型、H7亚型和H7N9流感病毒核酸检测;并对深圳市休市后一个月内全市人感染H7N9禽流感病例发病情况与广东省其他地区进行比较。结果共检测215份活禽市场外环境标本,检出A型流感病毒核酸阳性138份（64.19%）;其中H9、H5、H7亚型流感病毒核酸阳性分别为37份（17.21%）、24份（11.16%）和3份（1.40%,含1份H7N9禽流感病毒核酸阳性）;不同类型的外环境标本中不同的A型（χ^2=23.354,P=0.000）及H5（χ^2=10.609,P=0.005）亚型流感病毒核酸检出率有所不同;统一休市10 d后,深圳市1月内新发病例构成（6.67%）显著低于同期广东其它未休市地区的新发病例构成（46.55%）（χ^2=8.018,P=0.005）,活禽市场外环境中A型流感（χ^2=48.337,P=0.000）和H9亚型（χ^2=6.509,P=0.011）污染率显著下降;＂活禽零存栏＂措施可以有效降低活禽市场外环境中A型流感病毒的污染率（χ^2=5.465,P=0.019）。结论龙岗区活禽市场外环境存在一定的禽流感病毒污染,＂禁止活禽过夜和统一休市＂作为现阶段防控人感染H7N9禽流感疫情的主要措施是科学、有效的。

Objective To evaluate the effects of different management measures on control of contamination of live poultry markets by avian influenza virus through environmental monitoring. Methods Sixteen live poultry markets from 8 streets in Longgang District were selected for environmental monitoring of influenza A and H5,H9,H7,H7N9 subtypes by RT-PCR assay before and after united closure of live poultry markets in Shenzhen City from December 2014 to February 2015. The incidence of people infected with H7N9 in Shenzhen was compared with that of other parts of Guangdong Province within 1 month after 10-days closure of live poultry markets. Results Totally,215 environmental samples were detected. Influenza A and H9,H5,H7 subtypes were detected in 138,37,24 and 3 samples,with the positive rates of 64. 19%,17. 21%,11. 16% and 1. 40%,respectively. Only1 specimen was detected to be positive for H7N9. The positive rates of influenza A and H5 subtypes were different for different types of external environment specimens（ χ~2= 23. 354,P = 0. 000; χ~2= 10. 609,P = 0. 005,respectively）. The constituent ratio of new cases in Shenzhen（ 6.67%） within 1 month after 10-day united closure of live poultry markets was significantly lower than that of other parts of Guangdong Province（ 46. 55%）（ χ~2= 8. 018,P = 0. 005）. The contamination rates of external environment of live poultry markets by influenza A and H9 subtypes were significantly decreased（ χ~2= 48. 337,P = 0. 000; χ~2= 6. 509,P = 0. 011）. Strict implement of ＂zero live poultry in markets＂could effectively reduce contamination of external environment of live poultry markets by influenza A virus（ χ~2= 5. 465,P = 0. 019）. Conclusions Environmental contamination by avian influenza virus exists in Longgang District,and measures of＂zero live poultry in markets＂and unified closure of live poultry markets are scientific and effective for the prevention and control of H7N9 infection at the present stage.