Today, a study in Morbidity and Mortality Weekly Report describes a COVID-19 outbreak in the Hopi Tribe in Arizona that infected 29 of 60 people who attended two large indoor gatherings during tribal stay-at-home orders or were exposed at work or during family visits, sparking the creation of an enhanced coronavirus surveillance and education program detailed in an accompanying field report.Symptomatic but undiagnosed virus spreadersThe outbreak was detected on Jun 3, when a 73-year-old woman with symptoms was diagnosed as having COVID-19 11 days after she and a sibling together made a 2-hour drive to a large home improvement store, where they spent several hours.