重庆市部分地区H5和H7重组禽流感病毒二价灭活苗免疫效果监测

Immunological Effect Surveillance of Recombinant H5 and H7 Subtype Avian Influenza Inactivated Vaccine in Part Area of Chongqing City

2017年7月7日,农业部决定对全国家禽开展H7亚型流感免疫。为了掌握重组禽流感病毒(H5+H7)二价灭活苗的免疫效果,2017年8—9月,重庆市动物疫病预防控制中心进行了控制性试验和大面积临床监测。控制试验结果表明:首免15 d后,H7亚型禽流感抗体合格率可达70.00%,H5亚型抗体合格率仅为10.00%;首免22 d后,H7亚型禽流感抗体合格率达到93.33%,H5亚型抗体合格率达到60.00%;该疫苗未出现严重免疫副反应;H7亚型禽流感抗体产生的时间早于H5亚型。随机选取5个区县,采集414份免疫血清进行监测。结果显示:二价灭活苗免疫21 d后,H5和H7亚型禽流感抗体平均合格率分别为92.27%和76.00%;5个区县的抗体水平存在差异;蛋鸡抗体水平高于肉鸡。控制试验及临床监测结果提示,该疫苗免疫效果确实,但部分区县仍存在免疫抗体水平不高的养禽场。因此,在新旧疫苗交替使用期间,各地应高度重视高致病性H5和H7亚型禽流感防治工作,尤其是肉鸡。

On July 7 th of 2017,it was decided to carry out immunization of H7 subtype influenza vaccine towards poultry in China by the Ministry of Agriculture. In order to investigate the immune effects of divalent inactivated vaccine of recombinant Avian influenza virus(H5+H7),the control test and clinical monitoring in large area were carried out by Chongqing Animal Disease Prevention and Control Center from August to September in 2017. The results of control test showed that the qualification rate of antibodies against H7 subtype Avian influenza(AI)could reach 70.00 % on the 15 th day after first immunization,while against H5 subtype was only 10.00 %. On the 22 th day after first immunization,the qualification rate of antibodies against H7 subtype virus was 93.33 %,and against H5 subtype was 60.00 %. No serious immune side effects were found after vaccination,and the antibody production time of H7 subtype AI was earlier than that of H5 subtype. Subsequently,a total of 414 samples which were selected randomly from 5 counties and districts were tested. The results showed that,on 15 day after immunization,the antibody average qualification rates of H5 and H7 subtype AI were 92.27% and 76.00 %,respectively,and significant difference existed in the antibody level among the 5 counties and districts. In addition,the antibody level of the laying hens was higher than that of the broilers. As a conclusion,the surveillance results indicated that the immune effect of the vaccine was concrete,but a low level of immunization antibodies still existed in some farms of some districts and counties. Hence,during the alternate use of new and old vaccines,the prevention and control work for highly pathogenic avian influenza should be paid high attention to,especially the broilers.