Seroprevalence of Infection-Induced SARS-CoV-2 Antibodies — United States, September 2021–February 2022
Kristie E.N. Clarke, Jefferson M. Jones, Yangyang Deng, Elise Nycz, Adam Lee, Ronaldo Iachan, Adi V. Gundlapalli, Aron J. Hall, Adam MacNeil
Abstract
In December 2021, the B.1.1.529 (Omicron) variant of SARS-CoV-2, the virus that causes COVID-19, became predominant in the United States. Subsequently, national COVID-19 case rates peaked at their highest recorded levels.* Traditional methods of disease surveillance do not capture all COVID-19 cases because some are asymptomatic, not diagnosed, or not reported; therefore, the proportion of the population with SARS-CoV-2 antibodies (i.e., seroprevalence) can improve understanding of population-level incidence of COVID-19. This report uses data from CDC's national commercial laboratory seroprevalence study and the 2018 American Community Survey to examine U.S. trends in infection-induced SARS-CoV-2 seroprevalence during September 2021-February 2022, by age group.