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: ...

We've all heard of "the flu" but when it comes to types, subtypes and variants, influenza can get a bit complicated. According to the U.S. Centers for Disease Control and Prevention (CDC), nearly ...

Highly pathogenic avian influenza A(H5N1) viruses have caused widespread infections in dairy cows and poultry in the United ...

So far, the H5N1 virus isn't transmitted between people — but the CDC has found a mutation in a human case "concerning." ...

of bird flu. Researchers know of six subtypes of avian influenza A viruses that have caused human infections: H3 strains. This subtype affects many water birds around the world. In birds it ...

Novel vaccine platform improved protection against diverse influenza subtypes when tested in animal models and human ...

The first severe case of H5N1 bird flu was confirmed in Louisiana. Here is a map of other states that have been affected.