New paper in Science, A single mutation in bovine influenza H5N1 hemagglutinin switches specificity to human receptors. If that isn’t clear enough, here is the editor’s summary:
In 2021, a highly pathogenic influenza H5N1 clade 2.3.4.4b virus was detected in North America that is capable of infecting a diversity of avian species, marine mammals, and humans. In 2024, clade 2.3.4.4b virus spread widely in dairy cattle in the US, causing a few mild human cases, but retaining specificity for avian receptors. Historically, this virus has caused up to 30% fatality in humans, so Lin et al. performed a genetic and structural analysis of the mutations necessary to fully switch host receptor recognition. A single glutamic acid to leucine mutation at residue 226 of the virus hemagglutinin was sufficient to enact the change from avian to human specificity. In nature, the occurrence of this single mutation could be an indicator of human pandemic risk. —Caroline Ash
Time to stock up on Tamiflu and Xofluza.
Addendum: See also A Bird Flu Pandemic Would Be One of the Most Foreseeable Catastrophes in History
