here is a well-made video about the benefits of making and using face masks. . . . Made in a country with a low C19 infection and death count.
Similarly Taiwan, where anyone leaving home is required to wear a face mask. Currently 348 confirmed cases and five deaths attributed to COVID-19 on the island, which has a population of just under 24 million. Taiwan is not restricting movement to the extent of most countries, but my wife's brother, who lives in Taipei, told her this evening that the body temperature of anyone entering a business, government, or other public building is checked. (Singapore has essentially identical rules.)
The U.S. Centers for Disease Control and Prevention is now, somewhat belatedly, also recommending their use:
We now know from recent studies that a significant portion of individuals with coronavirus lack symptoms (“asymptomatic”) and that even those who eventually develop symptoms (“pre-symptomatic”) can transmit the virus to others before showing symptoms. This means that the virus can spread between people interacting in close proximity—for example, speaking, coughing, or sneezing—even if those people are not exhibiting symptoms. In light of this new evidence, CDC recommends wearing cloth face coverings in public settings where other social distancing measures are difficult to maintain (e.g., grocery stores and pharmacies) especially in areas of significant community-based transmission.
In addition to preventing the spread of droplets from coughs or sneezes, a mask also reduces the risk that the wearer will unknowingly touch his or her face with a hand that has been in contact with a surface containing virus-laden droplets.