Bird flu has been invading the brains of mammals. Here’s why
H5N1 and its relatives are more likely to infect brain tissue than other kinds of flu
A National Fisheries and Aquaculture service employee wearing biosafety gear approaches a sea lion at a beach in Chile that was closed in May 2023 due to the spread of bird flu in the region. That year, at least 24,000 South American sea lions died from an H5N1 infection.