Bird flu latest: California declares emergency as US reports 1st severe human case

The first known severe case of bird flu in the U.S. has been reported in Louisiana, health officials said Wednesday. 

The Louisiana patient is older with underlying health conditions, and had been handling sick and dead birds, according to the U.S. Centers for Disease Control and Prevention.

Louisiana’s severe bird flu case was announced on the same day California's governor declared a state of emergency as the virus rampages through dairy cattle there. 

Louisiana patient is first severe bird flu case in US

FILE - A sign warning against entry to the the Powers Farm white turkey flock is seen as part of an effort to prevent exposure to avian influenza on November 14, 2022 in Townsend, Delaware. (Photo by Nathan Howard/Getty Images)

A person in Louisiana is hospitalized in critical condition with severe respiratory symptoms caused by a bird flu infection. The person, who is over 65 and has underlying medical problems, had been in contact with sick and dead birds in a backyard flock.

It's the first human case in the U.S. linked to exposure to backyard birds, according to the CDC.

RELATED: Bird flu infects more farmworkers than previously known, CDC says

The Louisiana illness comes weeks after Canadian officials reported that a teen in British Columbia was hospitalized with a severe case of bird flu. In both instances, the illnesses were caused by a strain of the virus found in wild birds, not in cattle, officials said.

On a call with reporters, CDC officials declined to answer a question about whether the new U.S. case and the Canada case had any similarities or differences.

California declares bird flu health emergency

In California, Gov. Gavin Newsom declared a state of emergency as cases of the virus were detected in dairy cows on Southern California farms. Previously, the virus had been detected in the state's Central Valley.

Of the 865 herds where bird flu has been detected, nearly 650 of them are in California. Raw milk from infected cattle was recalled late last month after the virus was found in samples sold in California stores.

RELATED: Bird flu detected in pig for 1st time in US: What it means for humans

On Wednesday, Los Angeles County health officials confirmed the deaths of two cats from bird flu infections after drinking the recalled raw milk.

"This proclamation is a targeted action to ensure government agencies have the resources and flexibility they need to respond quickly to this outbreak," Newsom said in a statement.

U.S. bird flu outbreak

Since March, more than 60 bird flu infections in people have been reported in the U.S., but previous illnesses have been mild and most have been detected among farmworkers exposed to sick poultry or dairy cows. In two cases — an adult in Missouri and a child in California — health officials have not determined how they caught it.

The virus has been detected in 865 dairy herds in 16 states. 

CDC officials said bird flu is still mainly an animal health issue and that the risk to the general public remains low. There has been no documented spread of the virus from person to person, said the CDC's Dr. Demetre Daskalakis.

Flu experts said the trajectory of the virus in people remains unclear, but they urged people who have contact with sick or dead birds to take precautions, including wearing respiratory and eye protection and gloves when handling poultry.

"We may see more cases of severe disease in the U.S. since cases seem to be growing more frequent," said Angela Rasmussen, a virus expert at the University of Saskatchewan in Canada.

HealthCaliforniaLouisianaNews