With reports of the first human death from bird flu in the US, some Americans are feeling an uncomfortable flashback to the early days of Covid-19, when infectious disease experts were talking about a new virus that was sending people to the hospital with respiratory infections.

The case in Louisiana is the first human death from bird flu in the U.S. during this current outbreak, but there was a death in Mexico back in May 2024 in a patient with no known exposure to farm animals. The case, much like the patient in Louisiana, was in a person with other underlying conditions, though it’s not clear what those may have been.

Bird flu, also known as avian influenza or H5N1, has infected more than 130 million birds over the past two years as it threatened commercial bird operations and recently led to the first human death in the United States.

The experiment of whether H5 can ever be successful in human populations is happening before our eyes,” Seema Lakdawala, a flu virologist at Emory University, told me. “And we are doing nothing to stop it.

In its announcement this week of the first human death from bird flu in the United States, health officials in Louisiana were quick to note that the patient was over age 65 and “reported to have underlying medical conditions.

Any time a person catches H5N1, or bird flu, their infection is a chance for the virus to mutate in the wrong direction. When someone dies from the bird flu—as an elderly Louisiana man did on Jan. 6,