What Contact Tracing Tells Us About Cluster Spread Of The Coronavirus And Protests

As the U.S. begins to open back up, coronavirus clusters — where multiple people contract the COVID-19 at the same event or location — are popping up all over the country. And despite drawing massive crowds, anti-police protests in Washington state weren't among those clusters.
"We did have a rally in Bellingham, which is our county seat, and there was also a protest, and we have not been able to connect a single case to that rally or to the protest, and what we're finding is in large part that's due to the use of masks," Erika Lautenbach, the director of the Whatcom County Health Department in Washington State, tells NPR's All Things Considered. "Almost everyone at the rally was wearing a mask, and it's really a testament to how effective masks are in preventing the spread of this disease."
For the clusters that have popped up, Lautenbach says the state has been using contact tracing to learn more about how they're contributing to the spread. For instance, they found that 14 cases were associated with a party of 100 to 150 people in early June. Subsequently, 15 more cases were associated with the original 14.