The United States is seeing a second peak in flu cases this season. After doctor’s office visits for flu dipped early this year, they jumped past the previous season peak at the end of last month, with a 30% test positivity rate — and there are still months to go.

Testing results from patients indicate that two strains of seasonal flu that are causing most illnesses — a Type A H1N1 and a Type A H3N2. Health officials are closely watching

For a second time this season, at least 41 states are reporting high or very high levels of the flu. Here's how to stay safe.

San Mateo County public health officials reported finding H5N1 bird flu in a pet cat and a backyard poultry flock.

H5N1, known as bird flu, has been found in San Mateo County this week, according to state and local health officials. San Mateo County officials said Thursday that bird flu was found in a stray cat in Half Moon Bay.

A second type of bird flu has been found in U.S. dairy cows for the first time, the U.S. Department of Agriculture announced Wednesday.

A branch of the H5N1 bird flu family tree that hadn't previously been seen in cattle has now been detected in dairy cows.