Since the start of the pandemic, research has shown that face masks are an effective way to prevent the spread of SARS-CoV-2, the virus that causes COVID-19. While official messaging has been confusing or contradictory at times, studies have indicated that the virus is airborne and can also spread through aerosolized droplets that people expel when they cough or speak, for example. Surfaces seem to be less of a risk for transmission, so face masks have been promoted as a prevention tool, or piece of personal protective equipment (PPE). The amount of virus that a person is exposed to may influence whether a person is infected, and if they are, how severe their infection is, making any mitigation strategy better than none.
Masks are effective at preventing the spread of infection
N95 masks have helped health care professionals stay safe while providing care to sick people for many years. This pandemic is no different. As with other infectious agents, it's advisable to use multiple strategies to reduce the likelihood of infection, and masks are one of them.
Even regular medical masks are effective too, and research recently reported in the American Journal of Infection Control has shown that they block at least 56 percent of cough aerosols and 42 percent of exhaled aerosols. However, creating a double mask by using a cloth mask overtop of a medical mask increased their effectiveness dramatically, blocking at least 85 percent of cough aerosols and 91 percent of exhaled aerosols.
In a study simulating a source of infection who is coughing and an exposed person breathing near them, double masking reduced the recipient's exposure by 96 percent.
The most effective masks are the ones that fit best
Multiple studies have shown that a better fit is the key to a more effective mask. The AJIC report found that if medical masks were braced, they blocked at least 95 percent of cough aerosols and 99 percent of exhaled aerosols. Another investigation reported in Science Advances also determined that while one- and two-layer masks provide some protection, three-layer masks were most effective.
Studies using models of dummies and various systems that are meant to mimic the gases expelled when a person expels air have indicated that masks mitigate the spread of aerosols. Since SARS-CoV-2 is a virus that can spread through an airborne route, masks are important in both preventing infected people from spreading the disease, and reducing an uninfected person's exposure to the virus. Get fitting tips here from the University of Colorado.
Masks can be worn during exercise
Research reported in the Journal of the American Medical Association showed that cloth or N95 masks don't case undue strain on the heart, even if they are worn while a person is exercising strenuously. They acknowledged that while masks may slightly impede exercise ability in some cases, most people should be able to wear a mask without much trouble even in the gym.
Fabric masks can be washed and reused
Masking is contributing to waste, so can they be reused? Yes! Masks that are made from fabric can be reused. fabric masks can be washed many times and retain their effectiveness. One study tried washing the masks 52 times to mimic a year of use, and they were still just as effective, though the report also noted that fit is important, and using them with a medical mask improved their filtration.
Disposable medical masks are not meant to be washed and don't hold up well against autoclaving or a soak in alcohol, and ultraviolet light doesn't always reach every contaminated surface. But scientists found that if masks are heated to 70º Celsius (158ºF), eliminated 99.9 percent of SARS-CoV-2 and other viruses that were tested, which meets FDA guidelines for decontamination.
Masks Protect Us From More Than COVID-19