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Updated 25 days ago
Indexed 13 minutes ago

2020-2021 Nationwide Blood Donor Seroprevalence Survey Combined Infection- and Vaccination-Induced Seroprevalence Estimates

CDC is collaborating with the National Institutes of Health (NIH), the Food and Drug Administration (FDA), Vitalant Research Institute (VRI), Westat Inc., and numerous blood collection organizations across the United States to conduct a nationwide COVID-19 seroprevalence survey of blood donors. This is the largest nationwide COVID-19 seroprevalence survey to date. De-identified blood samples are tested for antibodies to SARS-CoV-2 to better understand the percentage of people in the United States who have antibodies against SARS-CoV-2 (the virus that causes COVID-19) and to track how this percentage changes over time. Both SARS-CoV-2 infection and COVID-19 vaccines currently used in the United States result in production of anti-spike (anti-S) antibodies but only infection results in production of anti-nucleocapsid (anti-N) antibodies. Combined seroprevalence estimates the proportion of the population with evidence of previous SARS-CoV-2 infection, COVID-19 vaccination, or both. It estimates the proportion of the population with some presumed protection against infection with the virus that causes COVID-19. The term “combined seroprevalence” refers to the combined infection- and vaccination-induced SARS-CoV-2 seroprevalences. This is the population that has anti-S antibodies, regardless of the presence of anti-N antibodies.

This link connects to a webpage that displays the data from the Nationwide Blood Donor Seroprevalence Survey. It offers an interactive visualization available at

Additional information is available at:

Querying over HTTP

Splitgraph serves as an HTTP API that lets you run SQL queries directly on this data to power Web applications. For example:

curl \
    -H "Content-Type: application/json" \
{"sql": "
    SELECT *
    FROM \"cdc-gov/20202021-nationwide-blood-donor-seroprevalence-wi5c-cscz\".\"20202021_nationwide_blood_donor_seroprevalence\"
    LIMIT 100 

See the Splitgraph documentation for more information.

  • 20202021_nationwide_blood_donor_seroprevalence
Upstream Metadata