The bottom line is that wearing masks does help prevent spread, but needs to be done properly. I do want to emphasize an issue which seems to have caused confusion (based on what I encounter online and questions from my own patients). At one point the WHO recommended wearing masks if you are sick or exposed to those who are, but not necessarily if you are healthy and out in public. The CDC, on the other hand, recommended everyone wear a mask in public. The reason for the WHO’s caution on recommending everyone wear a mask was not because they don’t work, but because at the time the recommendation was made we were having a shortage. The thought was – if you are healthy and not around sick people, don’t take a mask away from a health care worker who is on the front lines. The WHO basically left it up to individual countries based on their needs and resources. In any case – wear an appropriate mask, do it properly, and do it consistently.

But masks are not a panacea. Hand washing is also critical. Do it thoroughly, do it often, and don’t touch your face with unwashed hands. Don’t touch any public surface if you don’t have to. Elbows are your friends.

And finally, social distancing is still essential, and the evidence shows that it works. But here also there are many details. Do we need three feet, six feet, or nine feet (1, 2, or 3 meters)? The greater the distance, the greater the efficacy, until you are completely out of droplet range. This is also where masks come into play, by reducing the spread of droplets. Not physically touching other people is now also the norm, and this is critical.

The question is now turning to this – for how long do we need to ban large gatherings?