NPR's Lulu Garcia-Navarro speaks to Jeremy Howard, a research scientist at the University of San Francisco, about how to decide what masks might be more effective in preventing COVID-19 infections.
Copyright 2021 NPR
NPR's Lulu Garcia-Navarro speaks to Jeremy Howard, a research scientist at the University of San Francisco, about how to decide what masks might be more effective in preventing COVID-19 infections.
Copyright 2021 NPR