Bird flu virus shows mutations in first severe human case in US

The U.S. Centers for Disease Control and Prevention (CDC) has reported signs of mutation in the first severe human case of bird flu in the United States, raising concerns about the virus's potential to become more transmissible among humans.

According to the CDC, a sample taken from a patient in Louisiana showed mutations in the gene responsible for the virus’s ability to attach to host cells. The agency made the announcement on Thursday.

As of Friday, the CDC has confirmed 66 human cases of bird flu across the country, though the actual number is likely higher. While most human cases have been mild, the ongoing H5N1 bird flu outbreak has devastated the U.S. egg industry and heightened fears of a potential pandemic.

The Louisiana case is "concerning," the CDC stated, but emphasized that no evidence of person-to-person transmission of bird flu has been detected.

Key Developments in the Bird Flu Outbreak

Officials are increasingly worried about the potential for bird flu to spark another global health crisis.

The CDC identified the Louisiana patient as being over 65 years old with underlying health conditions. The infection was linked to exposure to sick and dead birds in backyard flocks, according to the agency.

A similar mutation has also been reported in British Columbia, Canada, suggesting the virus may be adapting in multiple regions.

Bird Flu’s Impact on Eggs and Pet Food

The bird flu outbreak has significantly disrupted poultry supplies, driving egg prices to near-record highs as 2024 ends.

The average cost of a dozen Grade A large eggs climbed to $3.65 in November, up from $3.37 in October and $2.50 at the start of the year, according to the U.S. Bureau of Labor Statistics.

Additionally, bird flu concerns prompted a recall of pet food this week. Northwest Naturals recalled 2-pound bags of its Feline Turkey Recipe raw and frozen cat food, following the death of a cat linked to a batch contaminated with bird flu. The affected products have best-by dates between May 21, 2026, and June 23, 2026.