The U.S. winter virus season is in full force, and by one measure is the most intense in 15 years.

Flu weakens the immune system, making the lungs susceptible to bacterial infections like pneumonia. This overlap increases ...

While we often refer to it as "the flu," the influenza virus has several strains, with flu A and flu B considered the most ...

The flu can also cause a general feeling of fatigue or malaise, Ray says, as well as gastrointestinal issues like diarrhea ...

"Flu A, Flu A, Flu A," said Dr. Charu Sawhney ... And she's seen mycoplasma pneumonia, also known as walking pneumonia, which is a bacterial infection. Allergies also have been a problem with ...