A virologist explains that why this probably isn’t the big one — but that it’s a sign of bad things happening with 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?

Federal health officials have confirmed unsettling new details about the first United States case of severe bird flu,

Los Angeles County health officials have identified three more cats with presumptive H5N1; the source of the virus has not yet determined, but experts suspect raw meat.

The patient in Louisiana who was hospitalized with severe bird flu illness was found to have a mutated version of the virus. Doctors react and share their concerns.

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.

The Centers for Disease Control and Prevention (CDC) has confirmed the first severe case of bird flu in the United States, noting it has shown a “concerning” mutation, leaving health experts to warn about the risk of another pandemic.