As flu season ramps up in the U.S., influenza is not as simple as it first appears, with several different strains in play.

To round out the name, the viruses are given an H and N number to indicate a subtype. A full name might then look like this: ...

Wastewater testing found the virus in Phoenix, Surprise and Tempe. Here’s a guide to what that means.

New Type of Antibody Shows Promise Against Multiple Forms of Flu Virus Dec. 21 ... A responsible for the 2009 H1N1 pandemic -- pdm09 -- shows that the virus has passed from humans to swine ...

The virus in the first severe human bird flu case in the U.S. was found to have mutated. Newsweek's live blog is closed.

The number of people falling ill with flu is almost double that of the cases for the comparitive week last year, with health ...

More Americans are getting infected with seasonal influenza and seeking care, a regular occurrence this time of year.

Getting an updated flu vaccine and taking steps to prevent the spread of germs can help everyone stay safe during flu season.

Learn why antibiotics are not effective against influenza, and what better options exist for preventing and treating the flu.

Most seasonal flu viruses are influenza type A, which usually start earlier in the season, with type B viruses circulating later in the winter. Currently, A viruses, of H1N1 and H3N2, are ...