The flu is a contagious respiratory illness caused by influenza viruses that infect the nose, throat, and lungs. It can cause mild to severe illness, and at times can lead to death. The best way to ...

Common cold symptoms tend to affect the upper airways, like the nose, head, and throat. Learn how symptoms progress with a ...

A dangerous bird flu, in other words, was suddenly circulating in mammals—mammals with which people have ongoing, extensive ...

One of the worst flu seasons in years will linger this spring, CDC warns - The current flu season is one of the worst the U.S ...