Johns Hopkins H5N1 is a dynamic virus that poses an increasing threat in terms of spillover and pandemic potential. On January 6, the Louisiana Department of Health announced that a patient hospitalized last month for H5N1 avian influenza had died, becoming the first U.S. death from the virus. To make matters worse, samples taken from the individual suggest that the virus mutated within the patient after infection—meaning it had begun to adapt to infect humans better—raising new questions about H5N1’s pandemic potential.
There have been 66 confirmed human cases in the U.S., the majority of which have resulted from exposure while working on poultry or dairy farms. Most cases are mild, and the risk to the general public currently remains low, but the escalation of high mortality in other mammals is another red flag for public health experts.