On Friday, the US Centers for Disease Control and Prevention recommended that citizens should wear "non-medical, cloth masks" to help prevent the spread of the coronavirus. Previously, the CDC had recommended that only those with Covid-19 symptoms wear masks. The agency now recommends that those who aren't feeling sick should still wear a mask, though compliance is voluntary.

In a statement on its website, the CDC says: "Cloth face coverings fashioned from household items or made at home from common materials at low cost can be used as an additional, voluntary public health measure." The word "additional" is key here; sheltering in place is still the most effective way to protect yourself and those in your community, and the agency recommends maintaining 6-foot social distancing as the primary method of reducing exposure.

This new policy comes on the heels of new research about how the virus is transmitted, and with cases on the rise across the US, there's some evidence that people who aren't showing any symptoms can still be spreading the virus as they move about in public.

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This week, cities like New York and Los Angeles have also recommended that all residents wear face coverings in public, whether they're showing signs of sickness or not. Specific guidance has been issued for Los Angeles (and California as a whole) and New York City.

These policy recommendations are happening at a time when surgical face masks and N95 masks are already in critically short supply. This scarcity of protective equipment has been devastating for health care workers busy treating patients, and many fear that a nationwide decree to wear a mask could strain supplies even more.

If you live in a community where masks are recommended, or if you are caring for a loved one who's currently sick, you should make your own mask. Do not buy N95 masks, and absolutely do not hoard supplies that medical professionals need.

It's important to remember that cloth face coverings like those recommended by California's Department of Public Heath may help unknowingly infected people from transmitting the virus, but there is no guarantee they can prevent a healthy person from becoming infected.

Staying Home Is Still Most Important

Wearing a mask is a last-resort measure. A mask is not a virus-blocking solution that will allow you to return to normal social interactions. We all still need to stay home as much as possible until shelter-in-place orders have lifted.

If you do have to go outside for supplies, stay 6 feet away from other people, and continue washing your hands and disinfecting your home.

How Long Does the Coronavirus Live on Surfaces? Plus: What it means to “flatten the curve,” and everything else you need to know about the coronavirus.

So what should you wear? According to the CDC, a well-made mask that is snugly secured around the ears is best. Alternatively, any type of face covering like a bandana or scarf is better than nothing if you have to go out, although the CDC cautions that these are not considered proper protective gear and should only be used as a last resort. In either case, you want to be sure your nose and mouth are securely covered from all sides so droplets can't escape.

Some health care workers have taken to wearing homemade masks over their N95 masks to lengthen its lifespan. A few hospitals have put out calls asking for home-sewn donations, like University Hospitals in Ohio, or Deaconess Hospital in Evansville, Indiana, which has also set up a nationwide database to connect heath care facilities in need with those who can make masks and donate them. If you can sew, consider making and donating face masks to your local hospital.

The online marketplace Etsy has also asked its sellers to switch to making masks, but has offered crafters a number of precautions, like forbidding them to resell medical equipment and telling them not to make medical claims about home-sewn masks.

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