Researchers conducted spike protein antibody tests from 8,058 participants who were previously undiagnosed with COVID-19. Blood samples were collected between May 10 and July 31, 2020.
Of those, 304 had COVID-19 antibodies, translating to 4.8 million undiagnosed infections for each diagnosed case during this time period. This suggests there were potentially 16.8 million undiagnosed COVID-19 infections by mid-July — about five times higher than the 3 million official diagnosed cases at the time, according to the findings.
A higher proportion of Black participants (14.2 percent) had COVID-19 antibodies, compared to white (2.4 percent) and Asian (2 percent) participants.
“Our data suggests a larger spread of the COVID-19 pandemic in the United States during the first six months than originally thought,” researchers said. “Our findings have implications for understanding SARS-CoV-2 spread, epidemiological characteristics of spread and prevalence in different communities, and could have a potential impact on decisions involved in vaccine rollout.”
To view the full findings, click here.
