Virus

Necrotizing fasciitis is a rare, life-threatening illness caused by bacteria that aggressively attack the soft tissue of the body.

A teen in Canada may be the first person to catch an H5 bird flu virus within the country. Health officials are now working to confirm the diagnosis.

Rising H5N1 bird flu cases in the U.S. prompted the CDC to study the virus in ferrets, revealing it may have the potential to spread and cause severe symptoms in other mammals.

Scientists pinpointed 80 gene variants, including eight tied to fatty acid metabolism, that may cause breast cancer in some people, new research suggests.

The far-reaching impact of certain viruses on the body can make cells grow out of control, causing cancer.

As of now, 17 states have reported H5N1 bird flu cases in humans, but there is still no evidence for transmission between people. Could that change?

Experts explain how to shorten a flu infection.

The 2024-2025 COVID-19 vaccines are available, and the CDC recommends that certain groups get two doses, spaced six months apart.

Early experiments suggest a patch that delivers harmless electric currents into the skin can thwart certain bacterial infections. However, it has not yet been tested in humans.

U.S. health officials are investigating a multi-state outbreak of bacterial infections that has been linked to McDonald's Quarter Pounders.