How long do cold and flu germs stay alive after infected people cough and sneeze all over everything?
Answers from James M. Steckelberg, M.D.
It varies, depending partly on where the germ-laden droplets fall. Experiments with specific cold and flu germs have shown potential survival times ranging from a few minutes to 48 hours or more. How long such germs remain capable of infecting you in day-to-day life is harder to say.
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 have effects on how long cold and flu germs stay active outside the body.
It's easy to catch the flu or a cold from rubbing your nose after handling an object an infected person sneezed on a few moments ago. But personal contact with an infected person — a handshake, for example — 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.
Feb. 08, 2012
- Sakaguchi H, et al. Maintenance of influenza virus infectivity on the surfaces of personal protective equipment and clothing used in healthcare settings. Environmental Health and Preventative Medicine. 2010;15:344.
- Turner RB. Rhinovirus: Inactivation by physical and chemical means. In: Mandell GL, et al. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa.: Churchill Livingstone Elsevier; 2010. http://www.mdconsult.com/books/about.do?about=true&eid=4-u1.0-B978-0-443-06839-3..X0001-X--TOP&isbn=978-0-443-06839-3&uniqId=230100505-57. Accessed Dec. 29, 2011.
- Weber TP, et al. Inactivation of influenza A viruses in the environment and modes of transmission: A critical review. 2008;57:361.
- Yang W, et al. Dynamics of airborne influenza A viruses indoors and dependence on humidity. PLoS ONE. 2011;6:e21481. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0021481. Accessed Dec. 29, 2011.
- Brankston G, et al. Transmission of influenza A in human beings. Lancet Infectious Disease. 2007;7:257.
- CDC says "Take 3" actions to fight the flu. Centers for Disease Control and Prevention. http://www.cdc.gov/flu/protect/preventing.htm. Accessed Dec. 29, 2011.