The current strain of avian flu, H5N1, is responsible for the culling of millions of domestic birds and has sickened more than a dozen farmworkers in 2024^[1], most recently in Colorado^[2].

The Conversation U.S. asked immunologist and microbiologist^[3] Jenna Guthmiller^[4] from the University of Colorado Anschutz Medical Campus to explain the historical roots of H5N1, its mode of transmission and how to avoid coming into contact...