安徽省规模禽场高致病性禽流感血清学横断面研究与风险因素分析  

A Serological Cross-sectional Study on HPAI in Large-scale Poultry Farms in Anhui Province and Analysis on Relevant Risk Factors

作　　者：刘华[1,2] 占松鹤 何长生[1,2] 王倩 杨庆琳[1] 涂健 宋祥军[2] 祁克宗[2] 朱良强 Liu Hua;Zhan Songhe;He Changsheng;Wang Qian;Yang Qinglin;Tu Jian;Song Xiangjun;Qi Kezong;Zhu Liangqiang(Anhui Animal Disease Control and Preve.ntion Center,Hefei,Anhui 230091,China;Key Laboratory of Veterinary Pathobiology and Disease Prevention and Control of Anhui Province,Hefei,Anhui 230036,China)

机构地区：[1]安徽省动物疫病预防与控制中心,安徽合肥230091 [2]兽医病理生物学与疫病防控安徽省重点实验室,安徽合肥230036

出　　处：《中国动物检疫》2019年第12期1-7,共7页China Animal Health Inspection

基　　金：兽医病理生物学与疫病防控安徽省重点实验室自主（开放）课题;安徽省动物疫情监测与防治项目

摘　　要：为掌握安徽省禽群的禽流感免疫抗体水平以及引起免疫不合格的主要风险因素,在2018年春季集中免疫前,对安徽省7个市开展了H5和H7亚型禽流感血清学检测和问卷调查。按照分层随机抽样方法,在7个市选择种禽场、蛋禽场和肉禽场,共140个养禽场,在每个养殖场内随机抽取35份血清样品,进行HI抗体检测,并根据检测结果,计算群体水平的真实免疫合格率/阳性率;将H5或H7亚型禽流感抗体群体合格率低于70%的养禽场定义为免疫不合格场,进行单因素风险分析。结果显示:安徽省7个市H5(Re-8株)和H7N9(Re-1株)的场群真实抗体合格率/阳性率分别为67.7%(95%CI:60.0%~75.4%)和39.8%(95%CI:31.7%~47.9%),62个养禽场的H5或H7亚型抗体未达标(<70%);存栏量越小(P=0.046)、免疫次数越少(P=0.016),H5或H7亚型免疫抗体不合格的可能性越高(P<0.05);存栏量小于4000羽、免疫后时间≤21 d或≥91 d、家禽日龄≤26或≥2200、免疫次数≤1、规模化饲养鹅,以及不使用“H5+H7”二价灭活疫苗(OR=2.66,95%CI:1.34~5.35)、周边3 km内有野禽栖息地(OR=2.78,95%CI:1.10~7.65)的养禽场的H5或H7亚型免疫抗体不合格风险相对较高。结果表明:2018年春季安徽省7个市H5、H7亚型禽流感免疫抗体保护率下降幅度明显,需要及时开展春季集中免疫;养禽场规模、类型以及家禽种类、是否免疫疫苗、免疫次数、养禽场周边是否有野禽栖息地等,均与群体的禽流感免疫抗体合格率显著相关,因此在制定强制免疫计划时,应视情况进行分类指导,实时补免或增加免疫次数。此外,养禽场选址时应尽量避开野禽栖息地。本研究为决策部门制定禽流感免疫方案提供了技术支撑。In order to identify the level of antibody against highly pathogenic avian influenza(HPAI)in largescale poultry farms in Anhui Province and to analyze major risks that might lead to unqualified immunity,serological surveillance and questionnaire survey on H5 and H7 subtype HPAI were carried out in 7 cities prior to intensive vaccination in the spring of 2018.A total of 140 poultry farms including breeding,layer and broiler farms were selected to randomly collect 35 serum samples per farm using stratified random sampling method for hemagglutination inhibition test(HI),and then the true immune qualification rate/positive rate at the farm level was calculated according to the test results;the farms of which the qualification rate of antibody against H5 or H7 subtype virus was lower than 70%were defined as the ones with unqualified immunity,and then risk analysis on single factor was carried out.The results showed that the true immune qualification rates/positive rates of H5(Re-8 strain)and H7N9(Re-1 strain)at the farm level were 67.7%(95%CI:60.0%-75.4%)and 39.8%(95%CI:31.7%-47.9%),respectively;in 62 farms,the antibody level failed to reach the standard(less than 70%);the smaller the stock(P=0.046)and the less the vaccination frequency(P=0.016),the higher the probability of disqualification of immune antibodies(P<0.05).The high risk factors were as follows:the poultry stock was less than 4000,the period was within 21 days or above 91 days since last vaccination,the ages of live poultry were less than 26 days or more than 2200 days,the immunization times were less than or equal to 1,raising geese in a large scale,the poultry were not vaccinated with“H5+H7”bivalent inactivated vaccines(OR=2.66,95%CI:1.34-5.35),as well as there were wild bird habitats within 3 km radius around(OR=2.78,95%CI:1.10-7.65).Results showed that,the level of antibody against H5 and H7 subtype HPAI decreased obviously in the above 7 cities in the spring of 2018,hence it was necessary to carry out intensive vaccination in spring in time.The a

关 键 词：高致病性禽流感 H7N9 免疫 风险因素 安徽 

分 类 号：S851.3[农业科学—预防兽医学]