Group of US doctors write open letter to Biden begging his administration to manufacture and mail free N95 masks to EVERY American to protect against explosion of super-covid Physicians from Brigham and Women's Hospital and Harvard and the founder of a YouTube educational channel wrote a letter to the Biden team They said N95 masks, which protect against small virus particles, are the most effective at preventing coronavirus transmission The group called for an initiative to mass produce and mail a set of masks to each U.S. household every month It comes as more cases of the new UK variant of the virus are identified cross the country and the national vaccine rollout continues move slowly