毕英佐:H5流行毒株有变,2019疫苗毒株为Re-11z+Re-12株

一、2.3.4.4d分支成我国H5流感流行毒株2018年OIE的监测数据显示,高致病性禽流感在世界范围内的家禽和野鸟广泛流行。中国流行情况最为复杂,H5N1、H5N2、H5N6、H5N8和H7N9等禽流感亚型均有发生。2018年我国爆发的H5疫情以2.3.4.4d分支的H5N6为主,部分地区有2.3.2.1d分支的H5N1发生。

Protective efficacy of an H5/H7 trivalent inactivated vaccine produced from Re-11, Re-12, and H7-Re2 strains against challenge with different H5 and H7 viruses in chickens

We developed an H5/H7 trivalent inactivated vaccine by using Re-11, Re-12, and H7-Re2 vaccine seed viruses, which were generated by reverse genetics and derived their HA genes from A/duck/Guizhou/S4184/2017(H5N6) (DK/GZ/S4184/17) (a clade 2.3.4.4d virus), A/chicken/Liaoning/SD007/2017(H5N1) (CK/LN/SD007/17) (a clade 2.3.2.1d virus), and A/chicken/ Guangxi/SD098/2017(H7N9) (CK/GX/SD098/17), respectively. The protective efficacy of this novel vaccine and that of the recently used H5/H7 bivalent inactivated vaccine against different H5 and H7N9 viruses was evaluated in chickens. We found that the H5/H7 bivalent vaccine provided solid protection against the H7N9 virus CK/GX/SD098/17, but only 50–60% protection against different H5 viruses. In contrast, the novel H5/H7 trivalent vaccine provided complete protection against the H5 and H7 viruses tested. Our study underscores the importance of timely updating of vaccines for avian influenza control.

凌云乌鸡高致病性禽流感免疫抗体监测与效果分析

为了解凌云乌鸡高致病性禽流感免疫效果,分别对凌云乌鸡6个规模家禽养殖场和部分农村散养家禽户随机采集免疫后乌鸡血清样品,进行禽流感H_(5)Re-11株、H_(5)Re-12株、H_(7)Re-3株免疫抗体监测。检测结果显示,其抗体总体合格率分别为91%、93.23%、87.9%,H_(5)亚型免疫效果优于H_(7)亚型;凌云乌鸡规模场和农村散养户抗体合格率分别为94.23%、95.19%、92.78%和82.19%、87.67%、73.97%,规模养殖场的抗体合格率优于散养户。凌云乌鸡蛋鸡和肉鸡禽流感的抗体合格率分别为96.67%、98.33%、95%和87.75%、90.81%、82.99%,蛋鸡的抗体合格率比肉鸡高。免疫一次和免疫二次的抗体合格率分别为85.47%、88.89%、77.78%和96.67%、98.33%、99.16%,二次强化免疫H_(5)亚型和H_(7)亚型抗体合格率均90%,通过二次强化免疫,大幅度提高免疫抗体水平,极大地降低疫情发生风险。