There is first case of severe bird flu in the US, CDC confirms in H5N1 update

US has first case of severe bird flu, CDC confirms in H5N1 update

By Tanya Lewis edited by Dean Visser

The ongoing outbreak of bird flu in the United States is now even more concerning: A person in Louisiana has been hospitalized with the first serious case of infection with the H5N1 bird flu virus in the United States, the Centers for Disease Control and Prevention announced in a statement on Wednesday published.

A total of 61 human cases of H5N1 have been confirmed in the United States this year. Most of these occurred in workers on dairy or poultry farms – and most of them were mild. The latest Louisiana case, first reported by the Louisiana Department of Health last Friday, is the first known case of a person hospitalized for H5N1 infection in the United States this year. An investigation is underway, but the affected individual appears to have had contact with sick or dead birds in a backyard flock. The virus strain is different from the one currently circulating in dairy cows. Preliminary genetic sequencing found it was likely related to the D1.1 strain now circulating in wild birds and poultry in the United States, and to a human case in Canada.

In addition to the Louisiana case, Delaware recently reported a probable H5N1 case discovered during routine state flu surveillance. The infected person had no known contact with sick animals. The CDC was unable to confirm the type of influenza A virus after multiple tests and classified it as a “probable case.” There have been at least two previous cases with no known exposure.

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“These two cases do not change the CDC’s current risk assessment for the general population, which remains low,” Demetre Daskalakis, director of the CDC’s National Center for Immunization and Respiratory Diseases, said in a group call with reporters Wednesday. Still, “the large number of animals infected with H5 avian influenza – birds and mammals – increases the risk that the virus may potentially infect humans and potentially adapt to cause human-to-human transmission.”

H5N1 continues to infect dairy cows in at least 16 states, with 860 herds affected as of December 17. On December 6, the U.S. Department of Agriculture issued a new federal regulation for mass testing of raw milk from dairy cows. The order is being phased in in six states: California, Colorado, Michigan, Mississippi, Oregon and Pennsylvania. More states will be added as resources allow, Eric Deeble, USDA assistant undersecretary for marketing and regulatory programs, told reporters Wednesday. Several field trials for bovine H5N1 vaccines are underway at sites across the country, he added.

Also this week, the company Labcorp announced that it will now offer a human H5 bird flu test that doctors can order.