US reports first serious human case of bird flu

On By Littum

One person in Louisiana has been hospitalized with bird flu – the country’s first severe human H5N1 infectionaccording to the Centers for Disease Control and Prevention.

“The patient is experiencing severe respiratory illness related to H5N1 infection and is currently hospitalized in critical condition,” said Emma Herrock, a spokeswoman for the Louisiana Department of Health.

The CDC said the patient was likely exposed to the virus from a backyard flock, which would mark the first time such a flock has been linked to an avian flu infection in a U.S. resident.

“While an investigation into the source of this infection in Louisiana is ongoing, it is believed that the patient reported by Louisiana had been exposed to sick or dead birds on their property,” said Dr. Demetre Daskalakis, director of the National Center for Immunization and Respiratory Diseases, during a briefing on Wednesday.

The case was reported as a presumptive positive by Louisiana on Friday and later confirmed by CDC laboratory testing.

Daskalakis said the Louisiana Department of Health is conducting an investigation, monitoring the patient’s contacts for exposure and offering testing and antiviral medication as needed.

The patient is over 65 and had underlying medical conditions, Herrock said. She did not take a stand on questions about the patient’s symptoms or the backyard herd.

In the United States, 61 cases of bird flu in humans have been reported this year. No person-to-person transmission has so far been documented. Most cases have been mild and found among farm workers exposed to the virus through interactions with infected poultry or cattle. Common symptoms in past cases have included pinkeye, coughing and sneezing.

Dr. Peter Chin-Hong, a professor of medicine at the University of California San Francisco who studies infectious diseases, said the Louisiana case highlights the risk of off-farm exposure.

“We’ve focused on dairy workers and poultry workers, but a new risk is dealing with dead birds in your backyard,” he said.

Daskalakis said the CDC is still working to better characterize the virus’s genome, which will help researchers understand whether it has developed any mutations that could allow it to spread from person to person.

Early indicators in the Louisiana case suggest that the version of the virus causing the infection is similar to the one that has been circulating in wild birds and poultry in British Columbia, Canada and Washington state.

A teenager in British Columbia was hospitalized in November after contracting the same genotype of bird flu virus. Canadian health officials were unable to determine the source of the teenager’s infection.

“What this illustrates is that people can get really sick from bird flu, and to me it’s related to the case in British Columbia,” Chin-Hong said. “These patients are both united by the same variant.”

The CDC said the development does not change its assessment of H5N1’s immediate risk to public health, which it says remains “low.”

H5N1 began circulating widely among wild birds in the United States in 2022 and then spread to poultry farms and backyard flocks. At least 123 million birds have been killed or euthanized because of the virus since 2022, according to the CDC.

This spring, bird flu began spreading among dairy cows, and at least 16 states have since detected the virus in cows.

Research on dairy farms has shown that the virus can be spread efficiently between mammals. Researchers have found that it is likely to spread between livestock through raw milk because infected cows secrete large amounts of the virus through their mammary glands.

Although there is no evidence that the virus is spreading between humans, scientists are concerned that it could mutate and develop this ability, which could affect the next pandemic.

In the United States, there have been two cases so far in which health officials were unable to determine the source of a person’s exposure to bird flu. One was an infection in a California child reported in November. The other was in one inpatient in Missouriwho tested positive for H5N1 in August and recovered.

Daskalakis said the CDC considers the Louisiana case the first serious H5N1 infection because other conditions likely caused the hospitalization of the Missouri patient.