CDC confirms first ‘severe’ case of H5N1 bird flu in US

The CDC has declared the first “severe” case of H5N1 bird flu in the United States, according to a press release issued Wednesday. The good news? The person who contracted the virus appears to have acquired it from backyard chickens, meaning they did not acquire it through human-to-human transmission, which has long been feared as something that could fuel mutations and a new pandemic in humans. The bad news? Cases of bird flu in humans continue to tick up as the guy who mishandled America’s last pandemic is about to take back power.

The severe case announced by the CDC on Wednesday was first confirmed on Dec. 13 after tests came back for a patient in Louisiana, the agency said in a press release. The virus in this case was identified as genotype D1.1, which is related to other D1.1 cases that were found in humans from the state of Washington and British Columbia, Canada. That genotype is different from the B3.13 genotype detected in dairy cows throughout the United States that has been the dominant method of human infection. The state of California, which has the highest number of known dairy tree infections in the country at 645, declared a state of emergency on Wednesday.

D1.1 cases in humans have come from birds, although the new case in Louisiana is the first acquired from a backyard flock. Most human cases have come from agricultural workers exposed to commercial poultry. There was also a case in Missouri and a case in California where the route of infection had not been determined since they had no known exposure to farm animals. Recently wastewater detection of bird flu in several states such as Florida, Maine and New Jersey has also been perplexing since there are no known cases of infected birds or cattle in those states.

The CDC’s announcement Wednesday did not include any biographical information about the case in Louisiana The Washington Post reports that CDC officials have refused to provide even basic information about the timeline of how this person may have been infected or their symptoms. The only information shared in this regard is that they have symptoms consistent with the flu.

The CDC launched a online avian flu tracker which breaks down the confirmed cases in humans, as well as the states of the United States where they have been identified, and the animal that is believed to have been the source of the infection. There are a total of 61 confirmed cases in eight states, although suspected cases are not included. Delaware, for example, currently has a suspected case which has not been confirmed by the test. If this case is confirmed by the CDC Delaware will become the ninth state to see human cases of bird flu during this outbreak. Delaware also recently saw wastewater detection of the virus.

There have been no known human cases of bird flu acquired in the United States through the consumption of milk or beef, but this possibility has been a concern lately. Pasteurization kills avian influenza in milk, but a recent study has shown that the virus can survive five days in raw milk. Incoming President Donald Trump has tapped Robert F. Kennedy Jr., a vocal advocate of raw milk, to head the U.S. Department of Health and Human Services. Cats that were seen drinking raw milk recently in California have died and health officials in Los Angeles believe they were infected with bird flu.

Even with this new serious case of bird flu in Louisiana, the CDC remains firm in its belief that the threat to the broader population in the United States remains low.

“A sporadic case of severe H5N1 avian influenza disease in a person is not unexpected; infection with avian influenza A (H5N1) virus was previously associated with severe human disease in other countries during 2024 and previous years, including illness that resulted in death,” the CDC said in a statement.

“No person-to-person spread of H5 avian influenza has been detected,” the statement continued. “This case does not change CDC’s overall assessment of the immediate public health risk from H5N1 avian influenza, which remains low.”