山西省某灰雁养殖场H5N6高致病性禽流感暴发调查

An Outbreak Investigation on H5N6 Highly Pathogenic Avian Influenza in a Grey Goose Farm in Shanxi Province

2017年5月26日至6月5日,山西省某养殖专业合作社养殖的灰雁出现了发热、腹泻(拉黑绿稀便)、头颈后仰、失明等症状,并陆续死亡,共死亡625只,袭击率为52.08%(625/1 200),经国家禽流感参考实验室检测,确诊为H5N6亚型高致病性禽流感。采用问卷调查方式,对场内基本情况、免疫情况、调运情况及发病情况进行调查。调查发现,发病灰雁系5月26日调入,调运前未进行H5N6亚型禽流感免疫,因此调入时可能已感染禽流感病毒是此次暴发的主要原因。对全市范围的养殖禽类进行禽流感疫情排查,未发现其他疫情。调查结果提示:加强所有饲养禽类的禽流感免疫,建立有效的免疫屏障,对于控制禽流感疫情暴发具有重要意义;养殖场在购入禽类时,应认真查验检疫票证,了解免疫背景,并建立完善的养殖管理档案。

On 26 May,2017,clinical symptoms of fever,diarrhea(dark green loose stools),backward head and neck,and blindness occurred in grey geese in a professional breeding cooperative in Shanxi Province and the diseased geese died successively.Until June 5,a total of 625 gray geese died with an attack rate of 52.08%(625/1 200).Then a questionnaire survey was conducted from aspects of basic farm conditions,immunity state,allocation and transportation,and outbreak situation.And it was confirmed as H5N6 subtype highly pathogenic avian influenza by the National Avian Influenza Reference Laboratory.According to the survey,the main cause was that gray geese might have been infected with H5N6 subtype avian influenza due to lack of vaccination before being transported from the neighbor province on 26 May.Citywide investigation of avian influenza was then carried out towards poultry farms and no more infection was found.The survey results indicated the enhancement of avian influenza vaccination for poultry and the establishment of effective immunologic barrier would significantly contribute to the control of avian influenza infection.Moreover,the poultry farms should check the inspection and quarantine records carefully and recognize the vaccination background before buying poultry,and a sound breeding management archive should be set up.