The CDC recently updated its coronavirus guidelines to recommend the use of cloth face coverings in public settings where other social distancing measures are difficult to maintain – like at grocery stores and pharmacies.
Masks aren't just for those who have obvious symptoms of illness. A person may be contagious long before symptoms arise, and some may be infected and transmitting the virus without ever having symptoms.
We asked Jeanne Noble, UCSF assistant professor in emergency medicine, to explain how masks work, why they're important, and how to properly put on and take off different types of masks without contaminating yourself.
