Evidence map›Paper›PMID 37001559›Full record

ArticleJournal of the American Medical Directors Association2023

Protection from Omicron Infection in Residents of Nursing and Retirement Homes in Ontario, Canada.

Jessica A Breznik, Ahmad Rahim, Tara Kajaks, Megan Hagerman, Lucas Bilaver, Karen Colwill, Roaya M Dayam, Anne-Claude Gingras, Chris P Verschoor, Janet E McElhaney and 3 more

Open access · hybridAbstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in Journal of the American Medical Directors Association, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 8 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
8citing papers in PubMed, 1 pooled it
2.9field-weighted citation impact, top 9% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

8 citing papers in PubMed, 1 synthesis or guideline pooled it, 15 citations in OpenAlex.

  1. Globally approved vaccines for COVID-19: a systematic review.Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology] · 2025
    Pooled it
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

13 authors at 6 institutions in 1 country.

Jessica A BreznikMcMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada; Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada; Department of Medicine, Michael G. DeGroote School of Medicine, McMaster University, Hamilton, Ontario, Canada; McMaster Institute for Research on Aging, McMaster University, Hamilton, Ontario, Canada.
Ahmad RahimDepartment of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada.
Tara KajaksMcMaster Institute for Research on Aging, McMaster University, Hamilton, Ontario, Canada; Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada.
Megan HagermanMcMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada; Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada; Department of Medicine, Michael G. DeGroote School of Medicine, McMaster University, Hamilton, Ontario, Canada.
Lucas BilaverMcMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada; Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada; Department of Medicine, Michael G. DeGroote School of Medicine, McMaster University, Hamilton, Ontario, Canada.
Karen ColwillLunenfeld-Tanenbaum Research Institute at Mount Sinai Hospital Sinai Health, Toronto, Ontario, Canada.
Roaya M DayamLunenfeld-Tanenbaum Research Institute at Mount Sinai Hospital Sinai Health, Toronto, Ontario, Canada.
Anne-Claude GingrasLunenfeld-Tanenbaum Research Institute at Mount Sinai Hospital Sinai Health, Toronto, Ontario, Canada; Department of Molecular Genetics University of Toronto, Toronto, Ontario, Canada.
Chris P VerschoorMcMaster Institute for Research on Aging, McMaster University, Hamilton, Ontario, Canada; Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada; Health Sciences North Research Institute, Sudbury, Ontario, Canada.
Janet E McElhaneyHealth Sciences North Research Institute, Sudbury, Ontario, Canada; Posthumous.
Jonathan L BramsonMcMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada; Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada; Department of Medicine, Michael G. DeGroote School of Medicine, McMaster University, Hamilton, Ontario, Canada; Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada.
Dawn M E BowdishMcMaster Immunology Research Center, McMaster University, Hamilton, Ontario, Canada; Michael G. DeGroote Institute for Infectious Disease Research, McMaster University, Hamilton, Ontario, Canada; Department of Medicine, Michael G. DeGroote School of Medicine, McMaster University, Hamilton, Ontario, Canada; McMaster Institute for Research on Aging, McMaster University, Hamilton, Ontario, Canada; Firestone Institute of Respiratory Health, St Joseph's Healthcare, Hamilton, Ontario, Canada. Electronic address: bowdish@mcmaster.ca.
Andrew P CostaDepartment of Medicine, Michael G. DeGroote School of Medicine, McMaster University, Hamilton, Ontario, Canada; McMaster Institute for Research on Aging, McMaster University, Hamilton, Ontario, Canada; Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, Ontario, Canada; Centre for Integrated Care, St. Joseph's Health System, Hamilton, Ontario, Canada. Electronic address: acosta@mcmaster.ca.
McMaster University · CAImpact · CAMount Sinai Hospital · CAHealth Sciences North · CAPopulation Health Research Institute · CASt. Joseph’s Healthcare Hamilton · CA

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectivesTo identify factors that contribute to protection from infection with the Omicron variant of SARS-CoV-2 in older adults in nursing and retirement homes.

designLongitudinal cohort study with retrospective analysis of infection risk. SETTING AND

participants997 residents of nursing and retirement homes from Ontario, Canada, in the COVID in LTC study.

methodsResidents with 3 messenger RNA (mRNA) dose vaccinations were included in the study. SARS-CoV-2 infection was determined by positive nasopharyngeal polymerase chain reaction test and/or circulating antinucleocapsid IgG antibodies. Cumulative probability of Omicron infection after recent COVID-19 was assessed by log-rank test of Kaplan-Meier curves. Cox regression was used to assess risk of Omicron infection by age, sex, mRNA vaccine combination, whether individuals received a fourth dose, as well as recent COVID-19.

resultsIn total, 171 residents (17.2%) had a presumed Omicron variant SARS-CoV-2 infection between December 15, 2021 (local start of the first Omicron wave) and May 3, 2022. Risk of Omicron infection was not different by age [hazard ratio (95% confidence interval) 1.01 (0.99‒1.02)], or in women compared with men [0.97 (0.70‒1.34)], but infection risk decreased 47% with 3 vaccine doses of mRNA-1273 (Moderna) compared with BNT162b2 (Pfizer) [0.53 (0.31-0.90)], 81% with any fourth mRNA vaccine dose [0.19 (0.12‒0.30)], and 48% with SARS-CoV-2 infection in the 3 months prior to beginning of the Omicron wave [0.52, (0.27‒0.99)]. CONCLUSIONS AND IMPLICATIONS: Vaccine type (ie, mRNA-1273/Spikevax vs BNT162b2/Cominarty), any fourth vaccine dose, and hybrid immunity from recent COVID-19, were protective against infection with the Omicron variant. These data emphasize the importance of vaccine type, and number of vaccine doses, in maintenance of protective immunity and reduction of risk of Omicron variant breakthrough infection. These findings promote continued public health efforts to support vaccination programs and monitor vaccine immunogenicity in older adults.

Indexed as

BNT162 VaccineCOVID-192019-nCoV Vaccine mRNA-1273AgedFemaleHumansLongitudinal StudiesMaleOntarioRetirementRetrospective StudiesSARS-CoV-22019-nCoV Vaccine mRNA-1273BNT162 VaccineCOVID-19hybrid immunitymRNA vaccineolder adultsOmicron

Identifiers

PMID37001559
PMCPMC10046272
OpenAlexW4361209810

What OpenQuestion holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.