COVID-19 - What Do Masks Do?

Lindsay: The incidence of COVID-19 increased markedly in all the schools, most strikingly during May. She says investigators estimated that masks prevented almost 12,000 cases among the school population over a 15 week period. Lindsey: It's important for our patients who are vulnerable immunologically to minimize exposure. Steve: How do we help these individuals be protected from the consequences of significant respiratory viral infection?