https://www.wired.com/story/its-time-to-face-facts-america-masks-work/

When you look at photos of Americans during the 1918 influenza pandemic, one feature stands out above all else: masks. Fabric, usually white gauze, covers nearly every face. Across the country, public health experts recommended universal mask-wearing and some cities ordered residents to wear them under penalty of imprisonment or fine. The Red Cross made thousands of cloth masks and distributed them for free. Newspapers published instructions for sewing masks at home. “Make any kind of a mask…and use it immediately and at all times,” the Boston commissioner of health pleaded. “Even a handkerchief held in place over the face is better than nothing.”

After the 1918 pandemic, the prophylactic use of masks among the general public largely fell out of favor in America and much of the West. The U.S. Centers for Disease Control and Prevention has almost never advised healthy people to wear masks in public to prevent influenza or other respiratory diseases. In the past few months, with medical supplies dangerously diminished, the CDC, U.S. surgeon general Jerome Adams, and the World Health Organization have urged people not to buy masks, paradoxically claiming that masks are both essential for the safety of healthcare workers and incapable of protecting the public from Covid-19.