Coronavirus: Antibody tests show COVID-19 infection rate 10 times higher than reported, CDC says

The number of people infected with the novel coronavirus in the U.S. is likely to be vastly underestimated, according to an analysis from the U.S. Centers for Disease Control and Prevention.

In a study published online Tuesday by JAMA Internal Medicine, scientists with the CDC said they performed COVID-19 antibody tests on routine blood samples collected from more than 16,000 people in 10 regions nationwide. The tests revealed that actual infection rates were between six and 24 times higher than the number of reported cases.

“The findings may reflect the number of persons who had mild or no illnesses or who did not seek medical care or undergo testing but who still may have contributed to ongoing virus transmission in the population,” researchers said in an abstract published online Tuesday.

"For most sites, it is likely that greater than 10 times more SARS-CoV-2 infections occurred than the number of reported COVID-19 cases; most persons in each site, however, likely had no detectable SARS-CoV-2 antibodies."

Dr. Robert Redfield, who heads the CDC, said earlier this month that testing likely missed 90% of the nation’s COVID-19 cases, CNN reported.

As of Tuesday afternoon, more than 14.7 million COVID-19 cases have been reported worldwide and more than 611,000 people have died of the viral infection, according to numbers compiled by Johns Hopkins University. The U.S. has been the hardest hit by the virus, with more than 3.8 million cases and over 141,000 deaths.