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Cited by 271

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Effectiveness of COVID-19 Vaccines in Preventing SARS-CoV-2 Infection Among Frontline Workers Before and During B.1.617.2 (Delta) Variant Predominance — Eight U.S. Locations, December 2020–August 2021

Open access
Fowlkes, Ashley, Gaglani, Manjusha, Groover, Kimberly, Thiese, Matthew S., Tyner, Harmony, Ellingson, Katherine, HEROES-RECOVER Cohorts·2021·MMWR. Morbidity and Mortality Weekly Report

Abstract

During December 14, 2020-April 10, 2021, data from the HEROES-RECOVER Cohorts,* a network of prospective cohorts among frontline workers, showed that the Pfizer-BioNTech and Moderna mRNA COVID-19 vaccines were approximately 90% effective in preventing symptomatic and asymptomatic infection with SARS-CoV-2, the virus that causes COVID-19, in real-world conditions (1,2). This report updates vaccine effectiveness (VE) estimates including all COVID-19 vaccines available through August 14, 2021, and examines whether VE differs for adults with increasing time since completion of all recommended vaccine doses. VE before and during SARS-CoV-2 B.1.617.2 (Delta) variant predominance, which coincided with an increase in reported COVID-19 vaccine breakthrough infections, were compared (3,4).

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Metadata

Authors
Fowlkes, A., Gaglani, M., Groover, K., Thiese, M. S., Tyner, H., Ellingson, K., & Cohorts, H.-R.
Venue
MMWR. Morbidity and Mortality Weekly Report
Published
2021-08-27
Volume
70
Issue
34
Pages
1167-1169
ISSN
  • 0149-2195 (ISSN-L)
  • 1545-861X
OpenAlex
W3193938173
Cited by
271
References
1
FWCI
18.73
Type
journal article
Language
en
Open access
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CoChat. (2026). Citation check: Effectiveness of COVID-19 Vaccines in Preventing SARS-CoV-2 Infection Among Frontline Workers Before and During B.1.617.2 (Delta) Variant Predominance — Eight U.S. Locations, December 2020–August 2021. https://app.cochat.ai/papers/10.15585/mmwr.mm7034e4
The paper
Fowlkes, A., Gaglani, M., Groover, K., Thiese, M. S., Tyner, H., Ellingson, K., & Cohorts, H.-R. (2021). Effectiveness of COVID-19 Vaccines in Preventing SARS-CoV-2 Infection Among Frontline Workers Before and During B.1.617.2 (Delta) Variant Predominance — Eight U.S. Locations, December 2020–August 2021. MMWR. Morbidity and Mortality Weekly Report. https://doi.org/10.15585/mmwr.mm7034e4

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Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.