Masks are an important part of the Coronavirus response, and while the messaging was conflicted at first – largely due to a lack of formal data, we are starting to get a pretty clear picture of their role. It was a misstep early on for the C.D.C. to tell the public masks were ineffective, when in fact they were trying to preserve the shelves from being ransacked for PPE.
Since then, we have seen many countries get COVID under control with universal mask participation among the populace, and now have a model and mammalian study. This in addition to the fact that doctors, construction workers and just about anyone who needs to keep things out of their lungs has used masks for their protection since cattle rustlers wore bandannas. This latest study tests the principle simply, with hamsters separated by surgical mask material: