Seroprevalence of anti-SARS-CoV-2 antibodies in a cohort of New York City metro blood donors using multiple SARS-CoV-2 serological assays: Implications for controlling the epidemic and "Reopening"

PLoS One. 2021 Apr 28;16(4):e0250319. doi: 10.1371/journal.pone.0250319. eCollection 2021.

Abstract

Projections of the stage of the Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) pandemic and local, regional and national public health policies to limit coronavirus spread as well as "reopen" cities and states, are best informed by serum neutralizing antibody titers measured by reproducible, high throughput, and statically credible antibody (Ab) assays. To date, a myriad of Ab tests, both available and FDA authorized for emergency, has led to confusion rather than insight per se. The present study reports the results of a rapid, point-in-time 1,000-person cohort study using serial blood donors in the New York City metropolitan area (NYC) using multiple serological tests, including enzyme-linked immunosorbent assays (ELISAs) and high throughput serological assays (HTSAs). These were then tested and associated with assays for neutralizing Ab (NAb). Of the 1,000 NYC blood donor samples in late June and early July 2020, 12.1% and 10.9% were seropositive using the Ortho Total Ig and the Abbott IgG HTSA assays, respectively. These serological assays correlated with neutralization activity specific to SARS-CoV-2. The data reported herein suggest that seroconversion in this population occurred in approximately 1 in 8 blood donors from the beginning of the pandemic in NYC (considered March 1, 2020). These findings deviate with an earlier seroprevalence study in NYC showing 13.7% positivity. Collectively however, these data demonstrate that a low number of individuals have serologic evidence of infection during this "first wave" and suggest that the notion of "herd immunity" at rates of ~60% or higher are not near. Furthermore, the data presented herein show that the nature of the Ab-based immunity is not invariably associated with the development of NAb. While the blood donor population may not mimic precisely the NYC population as a whole, rapid assessment of seroprevalence in this cohort and serial reassessment could aid public health decision making.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Antibodies, Neutralizing / blood
  • Antibodies, Viral / immunology
  • Blood Donors
  • COVID-19 / epidemiology*
  • COVID-19 / immunology
  • Cohort Studies
  • Enzyme-Linked Immunosorbent Assay / methods
  • Female
  • Humans
  • Immunoglobulin G / blood
  • Male
  • Middle Aged
  • New York City / epidemiology
  • SARS-CoV-2 / immunology*
  • SARS-CoV-2 / pathogenicity
  • Sensitivity and Specificity
  • Seroconversion / physiology
  • Seroepidemiologic Studies
  • Serologic Tests / methods
  • Spike Glycoprotein, Coronavirus / immunology

Substances

  • Antibodies, Neutralizing
  • Antibodies, Viral
  • Immunoglobulin G
  • Spike Glycoprotein, Coronavirus

Grants and funding

Funding for this project was provided by the New York Blood Center (NYBC) and Regeneron Pharmaceuticals, Inc (RPI). RPI provided support in the form of salaries for authors JH, MJ, SR, CK, AH, JH, MF and AB. RPI assisted with the design of the study, but did not have a role in data collection and analysis, decision to publish or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section. There was no additional external funding received for this study.