Evidence map›Paper›PMID 35858698›Full record

ArticleBMJ (Clinical research ed.)2022

Waning effectiveness of BNT162b2 and ChAdOx1 covid-19 vaccines over six months since second dose: OpenSAFELY cohort study using linked electronic health records.

Elsie M F Horne, William J Hulme, Ruth H Keogh, Tom M Palmer, Elizabeth J Williamson, Edward P K Parker, Amelia Green, Venexia Walker, Alex J Walker, Helen Curtis and 19 more

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

Article in BMJ (Clinical research ed.), 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 32 papers, 3 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
32citing papers in PubMed, 3 pooled it
6.1field-weighted citation impact, top 2% 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

32 citing papers in PubMed, 3 syntheses or guidelines pooled it, 62 citations in OpenAlex.

  1. Pooled it
  2. Pooled it
  3. Pooled it
  4. Trial
  5. Trial
  6. Article
  7. Article
  8. Article
  9. Article
  10. Article
  11. Mechanistic models of humoral kinetics following COVID-19 vaccination.Journal of the Royal Society, Interface · 2025
    Article
  12. Article
  13. Article
  14. Article
  15. Article
  16. Article
  17. Review
  18. Article
  19. Article
  20. Article
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

29 authors at 4 institutions in 2 countries.

Elsie M F HornePopulation Health Sciences, University of Bristol, Bristol, UK.ORCID 0000-0002-5545-7628
William J HulmeThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-9162-4999
Ruth H KeoghLondon School of Hygiene and Tropical Medicine, London, UK.ORCID 0000-0001-6504-3253
Tom M PalmerPopulation Health Sciences, University of Bristol, Bristol, UK.ORCID 0000-0003-4655-4511
Elizabeth J WilliamsonLondon School of Hygiene and Tropical Medicine, London, UK.ORCID 0000-0001-6905-876X
Edward P K ParkerLondon School of Hygiene and Tropical Medicine, London, UK.ORCID 0000-0001-5847-109X
Amelia GreenThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-7246-2074
Venexia WalkerPopulation Health Sciences, University of Bristol, Bristol, UK.ORCID 0000-0001-5064-446X
Alex J WalkerThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0003-4932-6135
Helen CurtisThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0003-3429-9576
Louis FisherThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-0295-3812
Brian MacKennaThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-3786-9063
Richard CrokerThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-8114-9186
Lisa HopcroftThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-7022-1322
Robin Y ParkThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.
Jon MasseyThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-2497-4040
Jessica MorleyThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0001-5221-4770
Amir MehrkarThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-2098-1278
Sebastian BaconThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-6354-3454
David EvansThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-1100-079X
Peter InglesbyThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.
Caroline E MortonThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0003-0783-0042
George HickmanThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-6691-4046
Simon DavyThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0001-9890-3619
Tom WardThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.
Iain DillinghamThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.
Ben GoldacreThe DataLab, Nuffield Department of Primary Care Health Sciences, University of Oxford, Oxford, UK.ORCID 0000-0002-5127-4728
Miguel A HernánCAUSALab, Harvard T.H. Chan School of Public Health, Boston, MA, USA.ORCID 0000-0003-1619-8456
Jonathan A C SternePopulation Health Sciences, University of Bristol, Bristol, UK.ORCID 0000-0001-8496-6053
University of Oxford · GBUniversity of Bristol · GBLondon School of Hygiene & Tropical Medicine · GBBoston University · US

Funding

Medical Research Council MC_PC_20030Medical Research Council MC_PC_20058Medical Research Council MC_PC_20059Medical Research Council MC_UU_00011/1Medical Research Council MR/S01442X/1Medical Research Council MR/S017968/1Medical Research Council MR/V015737/1Medical Research Council MR/W021420/1
6 · The paper itself

Abstract

objectiveTo estimate waning of covid-19 vaccine effectiveness over six months after second dose.

designCohort study, approved by NHS England.

settingLinked primary care, hospital, and covid-19 records within the OpenSAFELY-TPP database.

participantsAdults without previous SARS-CoV-2 infection were eligible, excluding care home residents and healthcare professionals. EXPOSURES: People who had received two doses of BNT162b2 or ChAdOx1 (administered during the national vaccine rollout) were compared with unvaccinated people during six consecutive comparison periods, each of four weeks.

main outcome measuresAdjusted hazard ratios for covid-19 related hospital admission, covid-19 related death, positive SARS-CoV-2 test, and non-covid-19 related death comparing vaccinated with unvaccinated people. Waning vaccine effectiveness was quantified as ratios of adjusted hazard ratios per four week period, separately for subgroups aged ≥65 years, 18-64 years and clinically vulnerable, 40-64 years, and 18-39 years.

results1 951 866 and 3 219 349 eligible adults received two doses of BNT162b2 and ChAdOx1, respectively, and 2 422 980 remained unvaccinated. Waning of vaccine effectiveness was estimated to be similar across outcomes and vaccine brands. In the ≥65 years subgroup, ratios of adjusted hazard ratios for covid-19 related hospital admission, covid-19 related death, and positive SARS-CoV-2 test ranged from 1.19 (95% confidence interval 1.14 to 1.24)to 1.34 (1.09 to 1.64) per four weeks. Despite waning vaccine effectiveness, rates of covid-19 related hospital admission and death were substantially lower among vaccinated than unvaccinated adults up to 26 weeks after the second dose, with estimated vaccine effectiveness ≥80% for BNT162b2, and ≥75% for ChAdOx1. By weeks 23-26, rates of positive SARS-CoV-2 test in vaccinated people were similar to or higher than in unvaccinated people (adjusted hazard ratios up to 1.72 (1.11 to 2.68) for BNT162b2 and 1.86 (1.79 to 1.93) for ChAdOx1).

conclusionsThe rate at which estimated vaccine effectiveness waned was consistent for covid-19 related hospital admission, covid-19 related death, and positive SARS-CoV-2 test and was similar across subgroups defined by age and clinical vulnerability. If sustained to outcomes of infection with the omicron variant and to booster vaccination, these findings will facilitate scheduling of booster vaccination.

Indexed as

COVID-19SARS-CoV-2AdultBNT162 VaccineChAdOx1 nCoV-19Cohort StudiesCOVID-19 VaccinesElectronic Health RecordsHumansBNT162 VaccineChAdOx1 nCoV-19COVID-19 Vaccines

Identifiers

PMID35858698
PMCPMC10441183
OpenAlexW4286009783

What OpenQuestion holds

Textmetadata
LicenceCC BY
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.