Here’s what to know about the United States’ first confirmed severe case of H5N1 avian influenza—and how to protect yourself.

The CDC has confirmed a total of 66 human cases of bird flu across the United States as of Friday, although the number is believed to be higher.

The Centers for Disease Control and Prevention (CDC) has identified mutations in the H5N1 bird flu virus that may increase ...

H5N1 bird flu samples collected from a severely ill patient in ... One of the mutations was also seen in a sample from a British Columbia teenager who was hospitalized with bird flu, the CDC said.

The agency, in its latest update released Thursday, said the mutations were not found in samples taken from wild birds, suggesting the virus changed over the course of the patient’s infection.

commonly known as bird flu, less than a month after a child in California was diagnosed with the virus. On Friday, the CDC confirmed a person from Louisiana had avian influenza A virus, H5N1 ...