Wearing a mask is more for people already showing symptoms of coronavirus and their caregivers than for people trying to prevent it
The Centers for Disease Control and Prevention
said it "does not recommend that people who are well wear a facemask to protect themselves from respiratory diseases, including COVID-19," referring to the disease caused by the new coronavirus. Rather, experts caution that putting on a face mask without proper fitting and training could actually increase your risk.
"If it's not fitted right, you're going to fumble with it," explained Health and Human Services Secretary Alex Azar before a House Appropriations subcommittee on Wednesday. "You're going to be touching your face, which is the No. 1 way you're going to get disease, is unclean hands touching your face."
On the other hand, if you are already coughing and showing symptoms of possible coronavirus illness, that's when wearing a mask could be helpful for protecting those around you.
"The data on the effectiveness of masks for preventing respiratory virus infections is not very clear, " explains Dr. Andrew Stanley Pekosz of Johns Hopkins' Bloomberg School of Public Health. "The best data suggests that if you are ill and showing symptoms, wearing a mask can reduce the chances that you spread the virus to others."
Cloth surgical masks are not helpful at all
The common surgical mask you might be picturing in your head will not help you at all, Pekosz said.
A type called an N95 respirator mask, if properly fitted, can block large-particle droplets that may contain germs, but the
FDA warns they cannot filter out "very small particles in the air that may be transmitted by coughs [or] sneezes."
"An N95 mask is the one that is most practical," Pekosz tells CBS News. "It stops 95% of particles of a certain size. ... There is a N99 mask, which blocks 99% of particles, but that mask is difficult to wear for long periods of time because it is hard to breathe through it."
Respirator masks are more expensive. The
FDA also notes they are not designed to fit children or people with facial hair.
Even a good face mask isn't enough
"Masks shouldn't be considered to be the sole item that can protect you from infection, but it can be one of several things that can help you stay uninfected," said Pekosz.
"Wash your hands frequently. Practice social distancing — stay 5 feet away from people to avoid being close enough to be exposed to respiratory droplets from that person. More specific guidance will be given by the CDC soon, but those two things should be practiced by people on a daily basis to reduce the spread of respiratory viruses."
And he adds, "Get a flu shot — influenza has killed over 16,000 Americans this year and is still causing disease across the U.S."
You have to change masks every few hours
If you do go the mask route in spite of expert advice, it's important to note that face masks have a very specific lifespan. While there are some with longer lifespans or that have replaceable filters, the most common face masks on the market are disposable and single use. Each one of those is only good for a few hours.
"You want to change masks every few hours to make sure that they are functioning properly and aren't getting contaminated with virus particles on the outside," Pekosz tells CBS News. "It's not like putting one on protects you. One has to follow specific procedures to ensure you are using them effectively."
www.scmp.com
