美国威斯康星大学麦迪逊分校Yoshihiro Kawaoka课题组取得一项新成果。经过不懈努力，他们揭示了牛H5N1流感病毒的致病性和传播性。这一研究成果发表在2024年7月8日出版的国际学术期刊《自然》上。

研究人员揭示了从感染小鼠和雪貂牛奶中分离出的高致病性禽流感H5N1病毒的特征。与其他高致病性禽流感H5N1病毒一样，牛H5N1病毒也会造成全身传播，包括传播到这两种动物的乳腺；不过，在一种较早的高致病性禽流感H5N1病毒分离株中也观察到了这种趋势。

重要的是，牛高致病性禽流感H5N1病毒与人上呼吸道中表达的唾液酸结合，并低效传播给暴露的雪貂（四只暴露的雪貂中有一只发生血清转换，但未检测到病毒）。因此，牛高致病性禽流感H5N1病毒可能具有利于在哺乳动物中感染和传播的特征。

据了解，高致病性H5N1禽流感病毒偶尔会感染哺乳动物，但通常不会产生传播。2024年春季，美国牛群中爆发了前所未有的高致病性H5N1禽流感，病毒在牛群内部和牛群之间传播，家禽和猫也受到感染，并波及人类，这共同表明公共卫生风险增加。

附：英文原文

Title: Pathogenicity and transmissibility of bovine H5N1 influenza virus

Author: Eisfeld, Amie J., Biswas, Asim, Guan, Lizheng, Gu, Chunyang, Maemura, Tadashi, Trifkovic, Sanja, Wang, Tong, Babujee, Lavanya, Dahn, Randall, Halfmann, Peter J., Barnhardt, Tera, Neumann, Gabriele, Suzuki, Yasuo, Thompson, Alexis, Swinford, Amy K., Dimitrov, Kiril M., Poulsen, Keith, Kawaoka, Yoshihiro

Issue&Volume: 2024-07-08

Abstract: Highly pathogenic H5N1 avian influenza (HPAI H5N1) viruses occasionally infect, but typically do not transmit, in mammals. In the Spring of 2024, an unprecedented outbreak of HPAI H5N1 in bovine herds occurred in the US, with virus spread within and between herds, infections in poultry and cats, and spillover into humans, collectively indicating an increased public health risk1-4. Here, we characterized an HPAI H5N1 virus isolated from infected cow milk in mice and ferrets. Like other HPAI H5N1 viruses, the bovine H5N1 virus spread systemically, including to the mammary glands of both species; however, this tropism was also observed for an older HPAI H5N1 virus isolate. Importantly, bovine HPAI H5N1 virus bound to sialic acids expressed in human upper airways and inefficiently transmitted to exposed ferrets (one of four exposed ferrets seroconverted without virus detection). Bovine HPAI H5N1 virus thus possesses features that may facilitate infection and transmission in mammals.

DOI: 10.1038/s41586-024-07766-6

Source: https://www.nature.com/articles/s41586-024-07766-6