The U.S. Centers for Disease Control and Prevention said on Wednesday that a patient has been hospitalized with a severe case of H5N1 infection in Louisiana, marking the first known instance of a severe human illness linked to the bird flu virus in the United States.

The case was confirmed by the agency on Friday, it said.

BIRD FLU CAUSES DEATHS OF CATS AND ZOO ANIMALS AS VIRUS SPREADS IN US

The CDC said that a sporadic case of severe H5N1 bird flu illness in a person is not unexpected as has previously been experienced in other countries during 2024 and prior years, including in cases that led to death. The agency said its assessment of risk to the public remains low.

The CDC said that partial viral genome data from the infected patient shows that the virus belongs to the D1.1 genotype, recently detected in wild birds and poultry in the United States and in recent human cases in British Columbia, Canada, and Washington state.

This genotype of the virus is different from the B3.13 genotype detected in dairy cows, human cases than multiple states, and some poultry outbreaks in the country, CDC said.

There have been a total of 61 human cases of H5 bird flu reported in the United States since April, according to the CDC.