Masks Remain Extremely Effective Indoors, But Are They Necessary Outside?

Scientists and public health experts agree that masks are effective at lowering the spread of the coronavirus indoors, where the vast majority of transmission is likely to occur.

But what about outside?

About two dozen states have statewide mask mandates that generally require people to wear masks outside when they're not able to stay at least 6 feet apart. Many cities have their own rules.

But with vaccinations accumulating, some health experts and journalists are arguing that now is a good time for authorities to ease up on outdoor mask requirements. Studies have linked transmission to indoor settings far more than outdoor ones, though data is limited and there are plenty of caveats.

Dr. Ashish Jha, dean of Brown University's School of Public Health, notes that case numbers aren't going down and they've been largely stagnant for the past month or two. But he says the situations driving it are groups of people gathering indoors without masks.