First Severe H5N1 Bird Flu Case in the US Confirmed in Louisiana

 

The United States has recorded its first severe case of H5N1 bird flu, with a Louisiana resident hospitalized after contracting the virus, the Centers for Disease Control and Prevention (CDC) confirmed on Wednesday.

The individual reportedly had contact with sick and dead birds from a backyard flock, marking the first documented transmission of avian influenza from such a source in the US. CDC official Demetre Daskalakis described the case as “notable.”

The Louisiana case is part of an ongoing effort to monitor and manage the spread of H5N1 in the US, where 61 confirmed and seven probable cases have been identified so far. The outbreak has prompted new testing measures, including mandatory testing of bulk milk to detect potential infections in dairy herds, as announced by the Department of Agriculture earlier this month.

California, the nation’s leading milk producer, declared a state of emergency on Wednesday to streamline its response to the outbreak. According to state data, 60% of California’s dairy herds—representing 649 herds—have tested positive for bird flu since August.

Governor Gavin Newsom stated the emergency declaration would enable greater flexibility in staffing, contracting, and resource allocation. “This shift from regional containment to statewide monitoring is necessary to address the outbreak’s escalation,” he added.

The Louisiana patient, whose condition is severe, tested positive for flu A before additional analysis revealed the presence of bird flu. While the CDC has not disclosed the patient’s symptoms or treatment details due to privacy concerns, Daskalakis confirmed that public health officials are investigating the case and monitoring potential exposures.

Another probable human case was reported in Delaware earlier this month. However, CDC confirmatory testing did not verify H5N1 infection, and the case has not been added to the national tally. Wastewater testing in Delaware recently detected the virus near Georgetown, a key area for poultry operations, though there have been no reported infections in poultry or livestock in the state.

Daskalakis emphasized that the general public’s risk remains low, though individuals who work closely with infected animals are at higher risk. “Precautions, including the use of respirators and immediate testing upon symptom development, are strongly advised,” he said.

The strain detected in Louisiana aligns with the variant affecting a teenager in British Columbia, who remains critically ill. This variant is commonly found in wild and domesticated birds and differs from the strain spreading in dairy cows. Genomic sequencing of the virus is ongoing.

No human-to-human transmission of H5N1 has been reported in the US during this outbreak, and officials have not revised vaccination strategies despite the government’s stockpile of millions of H5N1 vaccine doses.

While the CDC continues to investigate and manage current cases, the bird flu outbreak highlights the importance of vigilance in animal and human health monitoring. As surveillance efforts intensify, officials are working to mitigate risks and prevent further spread of the virus.

For now, the Louisiana case serves as a sobering reminder of the potential dangers posed by zoonotic diseases and the need for coordinated public health responses.