The CDC recommends wearing cloth face coverings in public settings where other social distancing measures are difficult to maintain (e.g., grocery stores and pharmacies) especially in areas of significant community-based transmission.
https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/diy-cloth-face-coverings.html
The CDC continues to study the spread and effects of the novel coronavirus across the United States. We now know from recent studies that a significant portion of individuals with coronavirus lack symptoms "asymptomatic") and that even those who eventually develop symptoms ("pre-symptomatic") can transmit the virus to others before showing symptoms.
https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/cloth-face-cover.html
Aaron Hamilton, M.D., of Cleveland Clinic says the following:
https://newsroom.clevelandclinic.org/2020/04/09/wearing-and-caring-for-a-cloth-face-mask/
"wearing a cloth mask can be useful in situations where social distancing is a challenge."
"When space is tight, or you're in an area where it's hard to be six feet apart, the cloth mask ultimately protects others from you that's really the idea behind it," he said. "It's an extension of public health and helping to reduce the spread of coronavirus in the community."
"Masks can help stop us from touching our faces, can be a visual reminder to use social distancing, and can also help cover a cough or sneeze."
Dr. Hamilton said people should still be following shelter-at-home orders, and reminds us a mask is meant as an extra layer of protection when venturing out for essential reasons - like food or to see the doctor.