The U.S. Centers for Disease Control and Prevention has found mutations in samples taken from a man infected with the first severe case of avian influenza in the United States, mutations that were not present in specimens collected from his infected backyard flock.
The agency began analyzing the samples after the patient—a resident of southwestern Louisiana, aged over 65—was confirmed last week as the first person in the United States with a severe case of H5N1 bird flu.
