Swine Flu (H1N1) and Face Masks

When and how to use face masks in home and community settings.

Medically Reviewed by Louise Chang, MD on August 10, 2009

News coverage of swine flu outbreaks almost always shows people wearing face masks. Do they really need them to protect against H1N1 swine flu? Do you?

Here's what you should know:

What Is a Face Mask?

  • Face masks are sold as surgical masks, dental masks, medical procedure masks, isolation masks, or laser masks. There are several designs; some tie around the head, some have elastic bands around the head, and others have ear loops. Price range: $10 to $15 for a box of 50.
  • Washable, reusable face masks should be used only if disposable masks are not available. But none of these reusable masks has been evaluated by the FDA and none can legally be sold to protect against disease.
  • N95 respirators are face masks that fit more tightly to the face. They filter out 95% of small particles when correctly fitted, although this isn't easy to do in the home setting. Price range: $10 to $60 for a box of 20.
  • Bottom line: Nobody knows whether face masks or respirators really protect against flu. The recommendations below, from the CDC, are experts' best guesses as to the best way to use them.

Do Face Masks Work Against Swine Flu?

  • There's limited evidence -- but no proof -- that face masks offer some protection against H1NI swine flu.
  • One study shows that when there's a sick family member in the house, other family members could cut their risk of getting sick by 60% to 80% by using face masks consistently and correctly -- in combination with frequent hand washing and avoiding close contact with the sick person.
  • Face masks rated as N95 masks -- technically called respirators -- should theoretically work better than surgical masks, which fit more loosely. But at least one study shows no difference in protection in household settings.
  • Ferret studies suggest that swine flu is spread by large droplets and not by small droplets. All face masks may protect against large droplets; N95 masks may protect against smaller, aerosolized droplets.
  • Studies consistently show that most people in household and community settings don't use face masks consistently or correctly.

Who Should Wear Face Masks During a Swine Flu Pandemic?

  • Wear a face mask (consider using an N95 respirator) if you must come into close contact with a sick person. "Close contact" means within 6 feet.
  • Wear an N95 respirator if helping a sick person with a nebulizer, inhaler, or other respiratory treatment.
  • If you've got the flu, wear a face mask before going near other people.
  • If you've got the flu and must leave home -- to see the doctor, for example -- wear a face mask.
  • If you are well, but live in a household with someone who has the flu, wear a face mask before going near other people. Why? You may be infected with the flu bug but don't yet have symptoms.
  • If swine flu is widespread in your community, you may consider wearing a face mask when in crowded settings.

How to Use a Face Mask During a Swine Flu Pandemic

  • Don't rely on a face mask as your only protection. Avoid crowds, avoid close contact with sick people, and wash your hands often -- even if you wear a mask. And to protect others if you're sick, observe cough/sneeze etiquette and stay home.
  • Before putting on a face mask, wash your hands thoroughly.
  • Don't touch the outside of the face mask while you're wearing it or when you take it off.
  • Use disposable face masks only once, then -- holding them by the bands or ties, not the front of the mask -- throw them in the trash. Don't let the used mask touch anything else.
  • After taking off a face mask, wash your hands thoroughly.
  • Before reusing a fabric face mask (note that these are NOT approved by the FDA), wash it in normal laundry detergent and tumble dry in a hot dryer.

Show Sources


CDC: "Interim Guidance for Novel H1N1 Flu (Swine Flu): Taking Care of a Sick Person in Your Home," July 8, 2009.

Department of Health and Human Services: "Interim Public Health Guidance for the Use of Facemasks and Respirators in Non-Occupational Community Settings during an Influenza Pandemic," May 2007.

MacIntyre, C.R. Emerging Infectious Diseases, February 2009; vol 15: pp 233-241.

Cowling, B.J. PloS One, May 2008.

Weiss, M.M. American Journal of Public Health, Supplement 1, 2007.

Jefferson, T. Cochrane Database Systematic Reviews, October 2007.

© 2009 WebMD, LLC. All rights reserved. View privacy policy and trust info