While face masks were not initially a part of COVID-19 prevention strategies , experts now believe they could play a role in reducing disease transmission by preventing asymptomatic carriers from spreading the disease, discouraging people from touching their faces, and reminding people to continue to practice social distancing and hand hygiene.

If you don't have a fabric mask on hand, you might be wondering if a bandana or scarf will suffice. The answer: Yes, but there are a few caveats. (ICYWW, there's also a cottage industry of fabric face masks on Etsy, and patterns for face masks appearing all over social media right now.)

The thicker the fabric, the better the face mask.

Though Dr. Shan Soe-Lin, PhD, has a collection of fabric face masks that she keeps in rotation, she has also used a large, thick shawl in a pinch. If you have a choice between a scarf and a bandana you should use a scarf, she says.

Then, you should wrap it around your face a couple of times, and tie it around your chin so it stays in place.

The thicker the better," Dr. Soe-Lin says. "Theres a lot of discussion now about what kind of homemade masks are best and whether bandanas, for instance, are really protective. I would say for bandanas, you should double them up if you can, because theyre so thin.

If you decide to cut up an old t-shirt and use it to make a face covering, you should also be sure there are two layers of fabric.

Make sure your DIY mask covers your nose and mouth.

Tie the fabric so it completely covers your nose and mouth, leaving no gaps between your face and the fabric, Dr. Soe-Lin advises.

Once you tie your scarf or bandana, it should stay tied tightly until you return home.

Other things to consider: You should also make sure you can remove the garment without touching your face, and you should be able to wash it daily or after every use.

Will fabric face masks really protect me from novel coronavirus?

As for whether fabric face coverings are effective protection against the novel coronavirus, the answer is yes, as long as you're also social distancing and washing your hands.

"If youre infected, especially if youre asymptomatic, it actually will keep in a lot of large droplets from sneezes or coughs, and if youre not infected, in addition to the social distancing and hand-washing, it will protect you from very large droplets," Dr. Soe-Lin says.

On a societal scale, if everyone covers their faces, those who are infected will keep viral droplets in, and those who are not infected will keep viral droplets out.

I think the great thing about masks is theyre the only intervention I can think of that's completely equitable," Dr. Soe-Lin says.

On the flip side, medical and surgical masks should be reserved for medical professionals battling COVID-19 in hospitals. (There's still a very serious mask shortage.) Anyone whos not a frontline health worker should absolutely not be wearing an N95 or surgical mask," Dr. Soe-Lin says.