菜市场H5N1流感禽间暴发与人群感染风险评估

Evaluation on risk of human AIV infection after a H5N1 subtype avian influenza epidemic in a food market

目的评估广东省广州市某肉菜市场H5N1型动物禽流感疫情暴发后人群感染禽流感病毒(AIV)的风险。方法疫情暴发后,对病死禽的密切接触者采集咽拭子,RT-PCR检测H5N1核酸,并进行7 d医学观察;对疫区人群进行流感样病例监测,对有流行病学接触史者采集咽拭子检测H5N1核酸;采集该市场内活禽屠宰人群、一般食物销售人群、普通买菜人群血液标本,应用血凝抑制试验及抗体中和试验检测H 5、H 9抗体。结果13名密切接触者咽拭子H 5核酸均为阴性,7 d医学观察期间均未出现异常症状。监测疫区内流感样病例3 971例,其中53例有流行病学史,其咽拭子H 5核酸均为阴性;共采集市场内各类人群血液标本176份,H 5抗体均为阴性,但家禽屠宰人群H 9抗体阳性率为21.05%,高于一般食物零售人员(1.59%)、食物购买人员(1.00%)。结论肉菜市场H5N1型禽流感暴发疫情未传播至人类,H5N1病毒禽-人传播能力有限,但活禽屠宰人员有较高AIV感染风险。

Objective To evaluate the risk of human H5N1 avian influenza virus（AIV） infection after a H5N1 subtype AIV epidemic in a food market of Guangzhou.Methods The H5N1 RT-RCR test of throat swab sample and a 7 days medical observation were conducted among contacts of poultry died of H5N1 AIV.The influenza-like case was monitored in epidemic area and N5N1 test of the throat samples was done for persons with AIV exposure history.The blood samples of poultry butchers,normal food retailers,and food buyers in the food market were collected for tests of hemagglutination inhibition and neutralization tests for H5-Ab and H9-Ab.Results Thirteen close contacts were H5N1 nucleic acid negative.Among 3971 influenza-like cases,53 had AIV exposure history,but all of them were H5N1 nucleic acid negative.All of the 176 serum samples were H5-Ab negative,but the H9-Ab positive rate in the poultry butchers（21.05%） was higher than that of in the normal food retailers（1.59%） and food buyers（1.00%）.Conclusion H5N1 subtype AIV didn＇t transmit to human in this epidemic,and the poultry-human transmission ability of H5N1 subtype AIV is very limited.But the poultry butchers in food market have a higher risk of AIV infection.