The H5N1 avian flu is circulating in cows and other mammals. Whether it will make a permanent leap to humans is another ...

Influenza viruses are shifty entities. A seemingly ingenious and sneaky way for viruses to make these leaps is by swapping ...

Influenza A is further divided into subtypes. You may have heard of H1N1 or H3N2 – those are the two dominant types of influenza A circulating right now, according to the CDC.

What does it mean to have flu A or flu B this season, and do these types of flu have the same symptoms? Here's what to know about the flu viruses.

Influenza A is further divided into subtypes. You may have heard of H1N1 or H3N2 – those are the two dominant types of influenza A circulating right now, according to the CDC.

Influenza A is further divided into subtypes. You may have heard of H1N1 or H3N2 – those are the two dominant types of influenza A circulating right now, according to the CDC.

Influenza A is further divided into subtypes. You may have heard of H1N1 or H3N2 – those are the two dominant types of influenza A circulating right now, according to the CDC.

The flu is spreading far and wide across the U.S. – and influenza A is largely to blame.

Influenza A is further divided into subtypes. You may have heard of H1N1 or H3N2 – those are the two dominant types of influenza A circulating right now, according to the CDC.

(NEXSTAR) – The flu is spreading far and wide across the U.S. – and influenza A is largely to blame. Of all the flu tests reported to the Centers for Disease Control and Prevention since the ...