Hundreds in US Could Already Be Infected by Coronavirus, Research Suggests

A stretcher is moved from an AMR ambulance to the Life Care Center of Kirkland, where one associate and one resident were diagnosed with COVID-19 on Feb. 29, 2020. Jason Redmon/AFP via Getty Images

Hundreds of people in the United States could already have the new coronavirus, experts found.

Researchers studied the genomes of two coronavirus infections in Washington state, one announced on Jan. 20 and the other reported on Feb. 28.