This is especially important because a significant number of people who are positive carriers of the coronavirus are asymptomatic—meaning they show none of the listed symptoms—and totally unaware of their status.
A recent study from the University of Hong Kong and the University of Maryland found that people infected with a viral illness leave droplets in the air 30 percent of the time after breathing while not wearing masks. On the other hand, all participants who wore masks blocked nearly 100 percent of the droplets.
Face masks are being recommended (or required) as a way to keep the wearer from infecting anyone they come into contact with. This doesn’t mean that wearing a mask makes you invulnerable to being infected by someone who isn’t. So it’s essential that everyone still practices social distancing and other measures, mask or no mask.
Researchers found that a sheet of tightly woven cotton — of 600 threads per inch — plus two sheets of chiffon, made from polyester and spandex, seemed to make the most effective combination, filtering out 80–99% of the particles, depending on their size.
How to wear masks and how NOT to wear them
To be used effectively, face masks should be worn so that they cover both your mouth and nose. If either of them are exposed, that largely defeats the purpose of wearing one in the first place.
Tip: You should always wash your hands before applying or removing a mask to avoid the spread of germs.
Because face masks are new and can sometimes feel inconvenient—for example, when they fog up glasses—people tend to try and find shortcuts. You may have seen—or done—these yourself.
Peter Hessler, a writer for The New Yorker, came up with names for the most common ways people try to cheat with masks: