@article{b63d8768f4f34815a250d487b5b66e5b,
title = "Comparative effectiveness of ChAdOx1 versus BNT162b2 covid-19 vaccines in health and social care workers in England: cohort study using OpenSAFELY",
abstract = "Objective: To compare the effectiveness of the BNT162b2 mRNA (Pfizer-BioNTech) and the ChAdOx1 (Oxford-AstraZeneca) covid-19 vaccines against infection and covid-19 disease in health and social care workers. Design: Cohort study, emulating a comparative effectiveness trial, on behalf of NHS England. Setting: Linked primary care, hospital, and covid-19 surveillance records available within the OpenSAFELY-TPP research platform, covering a period when the SARS-CoV-2 Alpha variant was dominant. Participants: 317 341 health and social care workers vaccinated between 4 January and 28 February 2021, registered with a general practice using the TPP SystmOne clinical information system in England, and not clinically extremely vulnerable. Interventions: Vaccination with either BNT162b2 or ChAdOx1 administered as part of the national covid-19 vaccine roll-out. Main outcome measures: Recorded SARS-CoV-2 positive test, or covid-19 related attendance at an accident and emergency (A&E) department or hospital admission occurring within 20 weeks of receipt of the first vaccine dose. Results: Over the duration of 118 771 person-years of follow-up there were 6962 positive SARS-CoV-2 tests, 282 covid-19 related A&E attendances, and 166 covid-19 related hospital admissions. The cumulative incidence of each outcome was similar for both vaccines during the first 20 weeks after vaccination. The cumulative incidence of recorded SARS-CoV-2 infection 20 weeks after first-dose vaccination with BNT162b2 was 21.7 per 1000 people (95% confidence interval 20.9 to 22.4) and with ChAdOx1 was 23.7 (21.8 to 25.6), representing a difference of 2.04 per 1000 people (0.04 to 4.04). The difference in the cumulative incidence per 1000 people of covid-19 related A&E attendance at 20 weeks was 0.06 per 1000 people (95% CI-0.31 to 0.43). For covid-19 related hospital admission, this difference was 0.11 per 1000 people (-0.22 to 0.44). Conclusions: In this cohort of healthcare workers where we would not anticipate vaccine type to be related to health status, we found no substantial differences in the incidence of SARS-CoV-2 infection or covid-19 disease up to 20 weeks after vaccination. Incidence dropped sharply at 3-4 weeks after vaccination, and there were few covid-19 related hospital attendance and admission events after this period. This is in line with expected onset of vaccine induced immunity and suggests strong protection against Alpha variant covid-19 disease for both vaccines in this relatively young and healthy population of healthcare workers.",
keywords = "BNT162 Vaccine, COVID-19 Vaccines, COVID-19/epidemiology, Cohort Studies, Health Personnel, Humans, SARS-CoV-2, Social Support, Viral Vaccines",
author = "Hulme, {William J.} and Williamson, {Elizabeth J.} and Green, {Amelia C.A.} and Krishnan Bhaskaran and McDonald, {Helen I.} and Rentsch, {Christopher T.} and Anna Schultze and John Tazare and Curtis, {Helen J.} and Walker, {Alex J.} and Tomlinson, {Laurie A.} and Tom Palmer and Horne, {Elsie M.F.} and Brian MacKenna and Morton, {Caroline E.} and Amir Mehrkar and Jessica Morley and Louis Fisher and Bacon, {Sebastian C.J.} and David Evans and Peter Inglesby and George Hickman and Simon Davy and Tom Ward and Richard Croker and Eggo, {Rosalind M.} and Wong, {Angel Y.S.} and Rohini Mathur and Kevin Wing and Harriet Forbes and Grint, {Daniel J.} and Douglas, {Ian J.} and Evans, {Stephen J.W.} and Liam Smeeth and Chris Bates and Jonathan Cockburn and John Parry and Frank Hester and Sam Harper and Sterne, {Jonathan A.C.} and Hern{\'a}n, {Miguel A.} and Ben Goldacre",
note = "Funding Information: Funding This work was supported by the UKRI (COV0076;MR/V015737/1) NIHR and Asthma UK-BLF and the Longitudinal Health and wellbeing strand of the National Core Studies programme (UKRI MRC MC_PC_20030 and MC_PC_20059). The OpenSAFELY platform is funded by the Wellcome Trust (222097/Z/20/Z). TPP provided technical expertise and infrastructure within their data centre pro bono in the context of a national emergency. BG{\textquoteright}s work on clinical informatics is supported by the NIHR Oxford Biomedical Research Centre and the NIHR Applied Research Collaboration Oxford and Thames Valley. BG{\textquoteright}s work on better use of data in healthcare more broadly is currently funded in part by: NIHR Oxford Biomedical Research Centre, NIHR Applied Research Collaboration Oxford and Thames Valley, the Mohn-Westlake Foundation, NHS England, and the Health Foundation; all DataLab staff are supported by BG{\textquoteright}s grants on this work. LS reports grants from Wellcome, MRC, NIHR, UKRI, British Council, GSK, British Heart Foundation, and Diabetes UK outside this work. KB holds a Wellcome Senior Research Fellowship (220283/Z/20/Z). HIM is funded by the NIHR Health Protection Research Unit in Immunisation, a partnership between Public Health England and London School of Hygiene and Tropical Medicine. AYSW holds a fellowship from the British Heart Foundation. EJW holds grants from MRC. RM holds a Sir Henry Wellcome Fellowship funded by the Wellcome Trust (201375/Z/16/Z). HF holds a UKRI fellowship. IJD holds grants from NIHR and GSK. TP receives support from the Integrative Epidemiology Unit which receives funding from the UK Medical Research Council and the University of Bristol (MC_UU_00011/1, MC_UU_00011/3, MC_UU_00011/4). Funders had no role in the study design, collection, analysis, and interpretation of data; in the writing of the report; and in the decision to submit the article for publication. Funding Information: Competing interests: All authors have completed the ICMJE uniform disclosure form and declare the following: BG has received research funding from Health Data Research UK (HDRUK), the Laura and John Arnold Foundation, the Wellcome Trust, the NIHR Oxford Biomedical Research Centre, the NHS National Institute for Health Research School of Primary Care Research, the Mohn-Westlake Foundation, the Good Thinking Foundation, the Health Foundation, and the World Health Organisation; he also receives personal income from speaking and writing for lay audiences on the misuse of science. IJD holds shares in GlaxoSmithKline (GSK). Publisher Copyright: {\textcopyright} Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY. No commercial re-use. See rights and permissions. Published by BMJ.",
year = "2022",
month = jul,
day = "20",
doi = "10.1136/bmj-2021-068946",
language = "English",
volume = "378",
journal = "The BMJ",
issn = "0959-8146",
publisher = "BMJ Publishing Group",
number = "8346",
}