Their data so far suggest that a lot of people have had Covid-19 without ever receiving a diagnosis. Confirmed case counts suggest that almost 7 percent of people in the U.S. have had the virus. Data from the arm of the study looking at blood from clinical laboratory tests from all 50 states, the District of Columbia, and Puerto Rico found rates of antibody positivity that at times ranged from under 1 percent in some states to 23 percent in New York.