2009-2011年环洞庭湖区主要活禽批发市场低致病禽流感监测情况

Surveillance of low pathogenicity avian influenza viruses in major live poultry wholesale markets around Dongting Lake Region,China,2009-2011

目的了解环洞庭湖区主要活禽批发市场低致病性禽流感病毒的分布和流行情况,为该地区活禽批发市场低致病性禽流感的防控措施提供一些依据。方法对在活禽批发市场上采集的拭子样品先由尿囊腔接种SPF鸡胚,然后用血凝试验(HA)测定所收集的尿囊液,对HA测定有滴度的再进行血凝抑制试验(HI)和RT-PCT方法相结合鉴定病毒的亚型。结果2009-2011年冬春季节,我们在环洞庭湖地区主要活禽批发市场上共分离到627株低致病性禽流感病毒,总的分离率为22.2%,其中鸭拭子低致病性禽流感病毒的分离率最高,达到24.6%,其次是鸡拭子,达到21.5%,鹅拭子为11%。在所监测的5家活禽批发市场中共分离到H3、H4、H6、H9、H10型和H11等6种亚型的低致病性禽流感病毒,其中H9、H6和H4亚型比较高,其分离率分别可达到11%、6.3%和3.4%。结论活禽批发市场中低致病性禽流感隐性带毒的情况普遍存在,其发生禽流感疫情的威胁较大。建议整顿规范市场经营管理,特别是要建立活禽交易市场定期休市制度。

The distribution and prevalence of low pathogenic avian influenza virus in major live poultry wholesale markets around the Dongting Lake region, China were investigated in our study to propose prevention and control measures on low pathogenic avian flu in the area of live poultry wholesale market. The samples were injected to SPF chicken embryos by allanto- ic cavity, and then the allantoic fluid were harvested and used for hemagglutination （HA）. If it was positive by HA, subtypes of the virus would be determined by hemagglutination inhibition （HI） and RT PCT. We isolated 627 low pathogenic avian in- fluenza viruses in major live poultry wholesale market around Dongting Lake region systematically in winter and spring during 2009-2011, and the total separation rate was 22.2%. The duck swab separation rate of low pathogenic avian influenza was the highest, which was 24.6 %, and the following was chicken swab that reached 21.5 ~, and the goose swab separation rate was 11%. We isolated 6 HA subtypes including H3, H4, H6, Hg, H10, and Hll in every live poultry wholesale market, and the separation rate of Hg, H6 and H4 subtypes was relatively high, which could reach 11%, 6. 3% and 3.4%, respectively. Those results indicated that recessive infection of low pathogenic avian influenza virus was serious in live poultry wholesale mar- ket around the Dongting Lake area, and it was a great threat to the occurrence of avian flu.