I posted this as a comment, worth putting out on my timeline.
The World Health Organization published a video on March 9, 2020 titled "When and how to wear medical masks to protect against the new coronavirus?" and features Dr. April Baller of the WHO Health Emergencies Programme.
In the description it states...
"If you do not have any respiratory symptoms, such as fever, cough, or runny nose, you do not need to wear a medical mask. When used alone, masks can give you a false feeling of protection and can even be a source of infection when not used correctly."
Interesting that the video is Unlisted. Hmm, I wonder why.
https://youtu.be/M4olt47pr_o