CDC Confirms 1st Severe US Case of Bird Flu In Louisiana

A person holds a test tube in this photo illustration, on Jan. 14, 2023. Dado Ruvic/Illustration/Reuters

Health officials have confirmed the first severe case of H5N1 bird flu in the United States, marking a pivotal moment in monitoring efforts for the virus.

The patient, a resident of southwestern Louisiana, was hospitalized after exposure to sick and dead birds in a backyard flock, according to a Dec. 18 statement from the Centers for Disease Control and Prevention.

Besides being the first severe case of H5N1 bird flu in the United States, it is also the first infection linked to exposure to a backyard flock.

The Louisiana Department of Health initially identified the case as a presumptive positive on Dec. 13. The CDC has since confirmed that the virus belongs to the D1.1 genotype, recently found in wild birds and poultry in the United States and in human cases in Canada.

This strain differs from the B3.13 genotype associated with outbreaks in dairy cows and human cases in other states.

Sporadic cases of severe H5N1 bird flu infections are not unexpected in the United States, according to the CDC, which noted that this type of virus has been linked in other countries to severe human illness including fatalities.

The CDC emphasized, however, that the public health risk from the virus is still low. No person-to-person transmission has been detected, and the case aligns with patterns seen globally where human infections typically result from direct contact with infected animals or their secretions.

Health officials urge people with occupational or recreational exposure to birds, poultry, or other potentially infected animals to exercise caution. Protective measures include wearing personal protective equipment and avoiding direct contact with sick or dead animals, the CDC advised.

The Louisiana Department of Health echoed these precautions, recommending that individuals avoid direct contact with sick or dead birds, animals, or their droppings, and keep pets away from these sources.

The state agency advises against bringing sick wild animals into homes, thoroughly cooking poultry, eggs, and other animal products, and avoiding unpasteurized products from potentially infected animals.

Outbreaks of H5N1 among wild birds and poultry have persisted across the United States since 2022, with 61 confirmed human cases reported nationwide in 2024.

Most infections have been linked to poultry farms or dairy operations, with the Louisiana case underscoring the potential risks posed by smaller-scale backyard flocks.