Colds and the Flu | Causes & Risk Factors


What causes colds and the flu?

Viruses cause colds and the flu. More than 200 different viruses can cause colds. Not as many viruses cause the flu. That's why there's a shot available for the flu and not for colds.


See a list of resources used in the development of this information.

Written by editorial staff

Reviewed/Updated: 02/14
Created: 01/96