How long do cold and flu viruses stay alive after people with the viruses cough or sneeze?

Answer From Pritish K. Tosh, M.D.

Cold, flu and other related viruses may stay infectious for several hours to days, depending on where their droplets fall. Viruses generally stay active longer on stainless steel, plastic and similar hard surfaces than on fabric and other soft surfaces. The amount of virus that lands on a surface, as well as the temperature and humidity of the environment, also determines how long cold, flu and other viruses stay active outside the body.

It's possible to catch the flu or a cold virus after touching an object that a person with one of these viruses sneezed or coughed on a few moments before. But close contact with a person who has one of these viruses — such as a handshake or breathing in droplets from a cough or sneeze — is the most common way these viruses spread. The COVID-19 virus also spreads in these ways.

To reduce the risk of catching or spreading viruses that cause colds, the flu or COVID-19:

  • Wash your hands frequently with soap and water for at least 20 seconds. Or use an alcohol-based sanitizer.
  • Get a flu vaccine every year. And get a COVID-19 vaccine, too.
  • Clean and disinfect high-touch surfaces, such as light switches and doorknobs, often.
  • Avoid touching your nose, mouth and eyes.
  • Avoid close contact with people who are ill.
  • Cover your mouth and nose with your elbow or a tissue when you cough or sneeze. Throw the tissue away and wash your hands right away.
  • Wear a face mask in indoor public spaces and outdoors where there is a high risk of COVID-19 virus transmission, such as at crowded events or large gatherings. Further mask guidance differs depending on whether you are fully vaccinated or unvaccinated.


Pritish K. Tosh, M.D.

Nov. 10, 2021