Effectiveness of Covid-19 Vaccines in Ambulatory and Inpatient Care Settings
New England Journal of Medicine·
- DOI
- 10.1056/nejmoa2110362
- PMID
- 34496194
- PMCID
- PMC8451184
- OpenAlex
- W3198593250
- Study type
- Journal article
- Publisher
- Massachusetts Medical Society
- Article type
- journal-article
- Integrity
- current
Why this research matters now
The article provides peer-reviewed evidence on COVID-19 vaccine effectiveness against severe and healthcare-seeking outcomes in US adults, including groups described as disproportionately affected by SARS-CoV-2 infection. Its topic and journal placement make it directly relevant for literature review and editorial context.
Structured evidence summary
Research question
To estimate how well authorized COVID-19 vaccines in the United States prevented laboratory-confirmed SARS-CoV-2 infection leading to hospitalization, ICU admission, or an emergency department or urgent care visit among adults aged 50 years and older.
Study design
Multistate test-negative study using molecular SARS-CoV-2 testing among people with COVID-19-like illness. Vaccine effectiveness was estimated with adjustment for vaccination propensity and other factors.
Population and setting
Adults aged 50 years and older in the United States, drawn from 41,552 hospital admissions and 21,522 emergency department or urgent care visits at 187 hospitals and 221 outpatient sites from January 1 to June 22, 2021.
Main findings
Full mRNA vaccination was reported as 89% effective against infection leading to hospitalization, 90% against ICU admission, and 91% against emergency or urgent care visits. Effectiveness was similar for BNT162b2 and mRNA-1273 and remained within 81% to 95% in adults 85 years or older, people with chronic medical conditions, and Black or Hispanic adults. Ad26.COV2.S showed 68% effectiveness against hospitalization and 73% against emergency or urgent care visits.
Public-health relevance
The article provides peer-reviewed evidence on COVID-19 vaccine effectiveness against severe and healthcare-seeking outcomes in US adults, including groups described as disproportionately affected by SARS-CoV-2 infection. Its topic and journal placement make it directly relevant for literature review and editorial context.
Important limitations
No explicit study limitations are stated in the supplied abstract. This summary is limited to the supplied single-article abstract and metadata, so the original paper is needed for decision-grade interpretation.
GIDS interpretation
This paper is readily discoverable as a peer-reviewed US study on COVID-19 vaccination and vaccine effectiveness. It can provide context for literature review, but the supplied abstract does not support any live surveillance interpretation.
Related GIDS surveillance
Literature context does not validate, explain, or change a surveillance signal. Exact and contextual relationships are shown separately.
Evidence relationships
This article has 8 auditable classifier relationships to diseases, places, topics, and study design.