In 2024, at least 66 human cases of bird flu have been reported in the United States, each one raising the risk of another pandemic like COVID-19. So far, most cases have been described as “mild,” which means they weren't hospitalized.

The first severe case of H5N1 bird flu was confirmed in Louisiana. Here is a map of other states that have been affected.

Public health officials have just reported the first known “severe” case of bird flu in the United States. There are now 61 confirmed cases across eight states. This week, the Centers for Disease Control and Prevention (CDC) announced that a person had been hospitalized with a “severe case” of bird flu.

The United States has confirmed its first known severe human infection of H5N1 bird flu, in a person in Louisiana believed to have contracted the virus through contact with sick or dead birds in a backyard flock.

Genetic samples from the patient contained mutations that could, in theory, help the virus better infect human cells.

The patient in Louisiana who was hospitalized with severe bird flu illness was found to have a mutated version of the virus. Doctors react and share their concerns.

As of December 30, the CDC has confirmed 66 human cases of the bird flu virus in the United States. Most of them were mild infections among dairy workers and others who had contact with infected animals.