Five years after Donald Trump declared a national COVID emergency, here's what the research says about face masks.

The coronavirus outbreak around the globe has led to a shortage of protective face masks. The Centers for Disease Control and Prevention says healthcare workers should use homemade masks as a last ...

But the Food and Drug Administration has also approved some KN95 and FFP2 masks made in China and Europe that offer comparable protection. Disposable surgical masks are also made of non-woven fabric.

Of course, not all masks are created equal. Whereas pre-COVID, most of us not working in health care had never thought about ...