What Minnesota’s Protests Are Revealing About COVID-19 Spread

It seems that the recent protests in Minnesota and some other states didn't contribute materially to the spread of COVID-19. Infection rates among people who attended the protests are around 1 percent, which is about what epidemiologists would expect in the general population. This has implications for pandemic planning. 

Still, these early numbers are welcome news to Roger Shapiro, a professor of immunology and infectious diseases at Harvard’s T.H. Chan School of Public Health. “When I hear a 1 percent positivity rate, that’s encouraging to me that these protests are not representing new hot spots,” he says. That’s because 1 percent is around the background level of community transmission that might be expected if one were to test a large sample of randomly selected people.

Though Shapiro supports the protests, he was worried about their potential to seed new chains of infection. So why didn’t they? His hunch is that two things protected protesters against disease transmission more than some scientists expected: wearing masks and being outdoors. “I think we would have seen a very different situation with fewer masks and indoor events,” says Shapiro.

The article was published before Trump's recent rally in Oklahoma. It will be interesting to see whether there is a spike in cases in Tulsa, where the rally was held indoors and few people wore masks. We'll probably know by the weekend.