Preliminary analysis from 194 countries found that locations where masks were not recommended saw a 55% weekly increase in coronavirus deaths per capita after their first case was reported, compared to 7% in countries with crops or guidelines supporting the use of the mask. A University of Washington model also predicts that the United States could prevent at least 45,000 coronavirus deaths by November if 95% of the population wore masks in public.
However, not all masks provide equal levels of protection.
The ideal face mask blocks large respiratory droplets from coughing or sneezing – the primary method by which people transmit the coronavirus to others – as well as smaller airborne particles, called aerosols, produced when people speak or breathe out.
The World Health Organization recommends medical masks for healthcare workers, the elderly, people with underlying health conditions, and those who have tested positive or have symptoms of the coronavirus. Healthy people who don’t fall into these categories should wear a cloth mask, according to WHO. The Centers for Disease Control and Prevention also recommends cloth masks for the general public.
But even cloth masks vary, as some types are more porous than others.
“It depends on the quality,” Dr. Ramzi Asfour, infectious disease doctor in Marin County, California, told Business Insider. “If you make a fabric mask from Egyptian cotton 600 thread count sheets, it’s different from making it from an inexpensive T-shirt that isn’t very finely woven.” ”
Scientists have evaluated the most effective mask materials for trapping coronavirus in recent months. Here are their results so far – the list goes in order from most to least protective.