[Skip to Content]
Access to paid content on this site is currently suspended due to excessive activity being detected from your IP address Please contact the publisher to request reinstatement.
[Skip to Content Landing]
Views 21,166
Citations 0
July 21, 2020

Serosurveillance and the COVID-19 Epidemic in the US: Undetected, Uncertain, and Out of Control

Author Affiliations
  • 1Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston
  • 2Harvard Medical School, Boston, Massachusetts
  • 3Medical Practice Evaluation Center, Massachusetts General Hospital, Boston
JAMA. Published online July 21, 2020. doi:10.1001/jama.2020.14017

The true extent of the coronavirus disease 2019 (COVID-19) epidemic in the US is unknown. The 3.4 million confirmed cases reported (as of July 15, 2020) likely represent only a fraction of all the infections that have occurred in the US thus far. Limited laboratory capacity and restrictive testing guidelines early in the epidemic resulted in large numbers of undetected incident infections. Approximately 40% of all SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infections are thought to be asymptomatic,1 and active surveillance for infections without symptoms is limited even now, nearly 5 months after the first COVID-19 cases were reported in Seattle2 and Chicago.3 The true cumulative incidence of infection—a basic but critically important measurement—remains uncertain at a time when communities nationwide are struggling to navigate an ongoing, unprecedented public health emergency, and while apprehensions about the near-term and long-term trajectories of the epidemic loom large.