The deceased was over 65 and had other medical conditions, state officials said. A Louisiana patient who had been hospitalized with severe bird flu has died, the first such fatality in the United States, state health officials reported on Monday.

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,

The U.S. has experienced its first death from H5N1 bird flu. Here’s what happened, plus how concerned you should be, according to doctors.