Genetic analysis of H5N1 bird flu viruses from a severely ill patient in Louisiana revealed multiple mutations that may enhance the virus’s ability to bind to human upper airway cells, the Centers for Disease Control and Prevention (CDC) reported on Thursday.

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

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.

The CDC warns samples of the bird flu virus show signs of mutations that could make it more transmissible to humans. The CDC says it appears the H5N1 virus contained mutations in the Louisiana patient who contracted the nation’s first severe case of the illness.

The Centers for Disease Control and Prevention (CDC) has identified mutations in the H5N1 bird flu virus that may increase its ability to infect humans. These mutations, found in the hemagglutinin (HA) gene,

Health authorities have revealed that the bird flu virus mutated inside a Louisiana patient who contracted the first severe case of the illness in the US, potentially making it more transmissible to humans.