Federal health officials say that not only has a Louisiana resident contracted the first severe case of bird flu in the U.S., but that the virus likely mutated in the patient. The findings raise concern regarding the adaptability of the virus.

Amid a "concerning" new mutation in bird flu that may indicate the virus could begin to more easily infect humans, what are the symptoms to watch for and how worried should you be?

A genetic analysis suggests the bird flu virus mutated inside a Louisiana patient who contracted the first severe case of the illness in the United States. The U.S.

Tiny genetic alterations could help the bird flu virus enter cells in the upper respiratory tract, the C.D.C. said. But there is no sign that mutations are widespread in nature.

HPAI is considered low risk to humans, the agency said, and there have been no human cases in New England during the current outbreak. The post Bird flu detected in small backyard flock in Vermont appeared first on Boston.

A new bird flu mutation of H5N1 has been discovered in a patient in the US state of Louisiana. Public health officials are concerned the new strain may rapidly develop, increasing its ability to affect humans.