How long do cold and flu germs stay alive after infected people cough or sneeze?

Answers from James M. Steckelberg, M.D.

Cold and flu germ-laden droplets may remain infectious for several hours, depending on where they fall. Germs generally remain active longer on stainless steel, plastic and similar hard surfaces than on fabric and other soft surfaces. Other factors, such as the amount of virus deposited on a surface and the temperature and humidity of the environment, also determine how long cold and flu germs stay active outside the body.

It's possible to catch the flu or a cold after handling an object an infected person sneezed or coughed on a few moments ago. But personal contact with an infected person — such as a handshake or breathing in droplets from a cough or sneeze — is the most common way these germs spread.

The best way to avoid becoming infected with a cold or flu virus is to wash your hands frequently with soap and water or with an alcohol-based sanitizer. Also avoid rubbing your eyes or biting your nails. Most importantly — get a flu vaccine every year.

Jan. 09, 2015 See more Expert Answers