The U.S. Centers for Disease Control and Prevention (CDC) announced on Thursday that samples from the country’s first severe bird flu case revealed mutations not present in samples from an infected backyard flock on the patient’s property.
The CDC’s analysis identified changes in the hemagglutinin (HA) gene, a crucial component of the virus responsible for binding to host cells. Despite these findings, the agency emphasized that the overall risk to the public remains low and unchanged.
The severe case, reported last week, involved a Louisiana resident over 65 years old who was hospitalized with a serious respiratory illness. The patient was infected with the D1.1 genotype of the virus, recently detected in wild birds and poultry in the U.S., rather than the B3.13 genotype previously identified in dairy cows, human cases, and some poultry across multiple states.
Although the mutations in the Louisiana patient are rare, they have been documented in severe cases in other countries. Notably, a similar mutation was reported in a severe case in British Columbia, Canada.
The CDC confirmed that no transmission from the Louisiana patient to other individuals has been identified.
