When the Unites States experienced an outbreak of swine flu in 2009, everyone was talking about how to reduce the spread of the infection. According to the Centers for Disease Control and Prevention (CDC), vaccinations were limited that year because the virus wasn't identified until manufacturers had already started producing the annual vaccine (CDC, 2009).

Health organizations reminded people of the importance of regular handwashing with warm water and soap. People who developed the flu were advised to stay home to recover and avoid spreading the virus to others. Then, some people started doing something most of us hadn't seen before: wearing surgical masks.

Does wearing a facemask help you avoid the flu virus? If so, are some masks better than others?

Studies Show Masks Do Help

For many years, scientists weren't sure if wearing a mask was effective at preventing the spread of viruses. However, recent studies suggest that they can help.

A 2008 study published in the International Journal of Infectious Disease concluded that when used correctly, masks are highly effective in preventing the spread of infections. Family members of children with flu-like illnesses who used the masks properly were 80 percent less likely to be diagnosed with the illness. The difference between types of masks used was insignificant (MacIntyre, 2008).

Another study published in the Annals of Internal Medicine reported similar results. Researchers looked at 400 people who had the flu. They found that family members cut their risk of getting the flu by 70 percent when they washed their hands often and wore surgical masks (Benjamin J. Cowling, 2009). 

A team of researchers from the University of Michigan recruited more than 1,000 students from residence halls. They assigned the student to groups: those who wore masks, those who wore masks and practiced hand hygiene, and those who did neither. The results showed that those who wore masks in residence halls and practiced good handwashing reduced their risk of flu-like illness by 75 percent. However, the study found no reduction in symptoms for mask use alone. This finding suggests that the use of masks should always be paired with regular handwashing (Allison E. Aiello, et al., 2011).

Different Types of Masks

If you are considering wearing a mask to protect against infections, there are two types you should know about.


These are fairly loose-fitting, disposable masks approved by the U.S. Food and Drug Administration (FDA) for use as medical devices. Doctors, dentists, and nurses often wear them while at work.

They prevent large droplets of bodily fluids that may contain viruses from escaping the nose and mouth. They also protect the wearer against splashes and sprays from others, such as those from sneezes and coughs. However, they do not prevent the inhalation of small, airborne contaminants.


These are certified by the CDC and the National Institute for Occupational Safety and Health (NIOSH). Respirators, also called N95 respirator masks, are designed to protect the wearer from small particles in the air that may contain viruses. The name comes from the fact that they can filter 95 percent of airborne particles (CDC, 2012). These N95 masks are also often used when painting or handling potentially toxic materials.

Respirators are selected to fit the wearer's face. They must form a proper seal so that no gaps allow airborne viruses in. Healthcare workers use them to protect against airborne infectious diseases such as tuberculosis and anthrax, because they protect against both large and small particles.

In general, respirators are considered more effective at preventing the flu virus than regular facemasks. However, studies have found both to be helpful.

Guidelines for Wearing Facemasks

In 2010, the CDC revised its healthcare setting guidelines for flu prevention to include facemasks and respirators. They recommend that healthcare workers wear facemasks when working with patients who have the flu. They also suggest offering facemasks to patients showing signs of respiratory infections. Respirators, however, are reserved for healthcare workers to wear during medical procedures (CDC, 2010). 

Facemasks can help reduce the spread of the flu—but only if when worn correctly and frequently. For example, several patients were excluded from the results of the 2008 study because they didn't wear their masks properly or when they should have (MacIntyre, 2008).

Here are some guidelines for proper mask-wearing:

  • Wear a facemask when coming within six feet of a sick person.
  • Position the strings to keep the mask firmly in place over the nose, mouth, and chin. Try not to touch the mask again until you remove it.
  • Wear a facemask before going near other people if you have the flu.
  • If you have the flu and need to see the doctor, wear a facemask to protect others in the waiting room.
  • Consider wearing a mask in crowded settings if the flu is widespread in your community or if you are at high risk for flu complications.
  • When you're done wearing the mask, throw it away and wash your hands. Do not wear a facemask more than once.
  • Wash your hands often.