Pathogenicity and transmission dynamics of bovine H5N1 influenza virus
A new study on the pathogenicity and transmissibility of the bovine H5N1 influenza virus has been published in Nature. This paper provides valuable insights into the characteristics and potential impact of this virus. The bovine H5N1 virus isolated from infected cow milk showed systemic spread in mice and ferrets, reaching the mammary glands of both species. The tropism of the bovine H5N1 virus was similar to that of an older HPAI H5N1 virus isolate. The bovine H5N1 virus bound to sialic acids expressed in human upper airways. The virus transmitted inefficiently to exposed ferrets, with only one out of four exposed ferrets seroconverting without virus detection, suggesting limited transmissibility. The Cow-H5N1 virus bound to both α2,3- and α2,6-linked sialic acids, indicating that the Cow-H5N1 virus may have the ability to bind to cells in the upper respiratory tract of humans. This is of concern as it suggests a possible increase in the potential of this virus to infect other mammals.
These findings indicate that the bovine H5N1 virus possesses features that may facilitate infection and transmission in mammals, representing a paradigm shift and increasing the pandemic potential of these viruses. The study emphasizes the need for continued surveillance, research, and preparedness to address the evolving threat of HPAI H5N1 viruses to both animal and human populations.