A genetic analysis suggests the bird flu virus mutated inside a Louisiana patient who contracted the nation’s first severe case of the illness, federal health officials said this week.
The U.S. Centers for Disease Control and Prevention (CDC) said its researchers compared viruses obtained from the Louisiana case to a virus that came from infected birds on the patient’s property.
The CDC said changes seen in the person were not present in the virus samples obtained from the birds, suggesting that mutations developed during the person’s infection.
“The changes observed were likely generated by replication of this virus in the patient with advanced disease rather than primarily transmitted at the time of infection,” the CDC report said….