How a gay community helped the CDC spot a COVID outbreak

A data scientist working in tech, Michael Donnelly became an amateur COVID-19 watcher early in the pandemic. (Photo: Jason LeCras for NPR)

The Centers for Disease Control and Prevention has a lot of ways to pick up on COVID-19 outbreaks, but those methods often take awhile to bear fruit.

Not so with the Provincetown, Mass., cluster that started around July Fourth weekend…