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Up-to-date Information: Up-to-Date Info : To find the latest CDC information on this topic go to: https://www.cdc.gov/coronavirus/2019-nCoV/index.html

Science brief: COVID-19 vaccines and vaccination

Supporting Files Public Domain
File Language:
English


Details

  • Corporate Authors:
    National Center for Immunization and Respiratory Diseases (U.S.). Division of Viral Diseases.
  • Description:
    Last updated July 27, 2021

    Key Points

    • All COVID-19 vaccines currently authorized in the United States are effective against COVID-19, including serious outcomes of severe disease, hospitalization, and death.

    • Available evidence suggests the currently authorized mRNA COVID-19 vaccines (Pfizer-BioNTech and Moderna) are highly effective against hospitalization and death for a variety of strains, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), and Delta (B.1.617.2); data suggest lower effectiveness against confirmed infection and symptomatic disease caused by the Beta, Gamma, and Delta variants compared with the ancestral strain and Alpha variant. Ongoing monitoring of vaccine effectiveness against variants is needed.

    • A growing body of evidence indicates that people fully vaccinated with an mRNA vaccine (Pfizer-BioNTech or Moderna) are less likely than unvaccinated persons to acquire SARS-CoV-2 or to transmit it to others. However, the risk for SARS-CoV-2 breakthrough infection in fully vaccinated people cannot be completely eliminated as long as there is continued community transmission of the virus.

    • Studies are underway to learn more about the effectiveness of Johnson & Johnson/Janssen vaccine.

    • At this time, there are limited data on vaccine effectiveness in people who are immunocompromised. People with immunocompromising conditions, including those taking immunosuppressive medications, should discuss the need for personal protective measures after vaccination with their healthcare provider.

    • This updated science brief synthesizes the scientific evidence supporting CDC’s guidance for fully vaccinated people and will continue to be updated as more information becomes available.

  • Content Notes:
    Key points -- Background -- COVID-19 vaccine efficacy and effectiveness -- Emerging SARS-CoV-2 viral variants and vaccine performance -- Conclusions.
  • Subjects:
  • Series:
    Science Brief
  • Document Type:
    Text
  • Genre:
    Webpage
  • Place as Subject:
    United States
  • Collection(s):
  • Main Document Checksum:
    urn:sha-512:25eb2fe8055ebba4c2c6558bd5de4582fcf27ce9a76ef117841a68914a139cde6866b84ab414f3664e7e1adb0dcd7edf749c9c67ee61f9cac1129518bed3890a
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  • File Type:
    Filetype[PDF - 306.53 KB ]
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