First Severe Human Case of Avian Influenza in U.S. Reported in Louisiana

A patient in Louisiana has been hospitalized with a severe case of avian influenza, according to the CDC.

This case marks the “first instance of severe illness linked to the virus in the United States. The case was confirmed by the Centers for Disease Control and Prevention (CDC) on Friday, December 13. Since April 2024, there have been a total of 61 reported human cases of H5 bird flu reported in the United States.”

Partial viral genome data shows that the patient is infected with “the D1.1 genotype related to other D1.1 viruses recently detected in wild birds and poultry in the United States and in recent human cases in British Columbia, Canada, and Washington state. This H5N1 bird flu genotype is different than the B3.13 genotype detected in dairy cows, sporadic human cases in multiple states, and some poultry outbreaks in the United States.”

This sporadic case of severe H5N1 bird flu is “not unexpected,” according to the CDC. The patient had exposure to “sick and dead birds in backyard flocks.” At this point, there still has been no detected human-to-human spread of H5 bird flu, and the CDC’s overall assessment remains that the threat to the public is low.

The agency suggests that people “should avoid contact with sick or dead animals” and to wear protective personal equipment (PPE) if contact needs to be made.