Effectiveness of heterologous ChAdOx1 nCoV-19 and mRNA prime-boost vaccination against symptomatic Covid-19 infection in Sweden: A nationwide cohort study.


Journal

The Lancet regional health. Europe
ISSN: 2666-7762
Titre abrégé: Lancet Reg Health Eur
Pays: England
ID NLM: 101777707

Informations de publication

Date de publication:
Dec 2021
Historique:
pubmed: 26 10 2021
medline: 26 10 2021
entrez: 25 10 2021
Statut: ppublish

Résumé

The effectiveness of heterologous prime-boost Coronavirus disease 2019 (Covid-19) vaccination is currently unknown. From individuals vaccinated with two doses against Covid-19 in Sweden until July 5, 2021 (N=3,445,061), we formed a study cohort including 94,569 individuals that had received heterologous ChAdOx1 nCoV-19 / BNT162b2 prime-boost vaccination, 16,402 individuals that received heterologous ChAdOx1 nCoV-19 / mRNA-1273 prime-boost vaccination, and 430,100 individuals that received homologous ChAdOx1 nCoV-19 / ChAdOx1 nCoV-19 prime-boost vaccination. In addition, 180,716 individuals were selected who were unvaccinated at the date of vaccination in the corresponding case. Unvaccinated individuals were censored at first dose of any vaccine. Baseline was the date of the second dose of any vaccine, with the same date in the corresponding unvaccinated individual. The outcome included incident symptomatic Covid-19 infection occurring >14 days after baseline. During a mean follow-up time of 76 (range 1-183) days, symptomatic Covid-19 infection was confirmed in 187 individuals with heterologous vaccine schedules (incidence rate: 2.0/100,000 person-days) and in 306 individuals from the unvaccinated control group (incidence rate: 7.1/100,000 person-days). The adjusted vaccine effectiveness was 67% (95% CI, 59-73, P<0.001) for heterologous ChAdOx1 nCoV-19 / BNT162b2 prime-boost vaccination, and 79% (95% CI, 62-88, P<0.001) for heterologous ChAdOx1 nCoV-19 / mRNA-1273 prime-boost vaccination. When combined and analysed together, the two heterologous vaccine schedules had an effectiveness of 68% (95% CI, 61-74, P<0.001) which was significantly greater (P The findings of this study suggest that the use of heterologous ChAdOx1 nCoV-19 and mRNA prime-boost vaccination is an effective alternative to increase population immunity against Covid-19, including against the Delta variant which dominated the confirmed cases during the study period. These findings could have important implications for vaccination strategies and logistics, and consequently in the battle against the Covid-19 pandemic.

Sections du résumé

BACKGROUND BACKGROUND
The effectiveness of heterologous prime-boost Coronavirus disease 2019 (Covid-19) vaccination is currently unknown.
METHODS METHODS
From individuals vaccinated with two doses against Covid-19 in Sweden until July 5, 2021 (N=3,445,061), we formed a study cohort including 94,569 individuals that had received heterologous ChAdOx1 nCoV-19 / BNT162b2 prime-boost vaccination, 16,402 individuals that received heterologous ChAdOx1 nCoV-19 / mRNA-1273 prime-boost vaccination, and 430,100 individuals that received homologous ChAdOx1 nCoV-19 / ChAdOx1 nCoV-19 prime-boost vaccination. In addition, 180,716 individuals were selected who were unvaccinated at the date of vaccination in the corresponding case. Unvaccinated individuals were censored at first dose of any vaccine. Baseline was the date of the second dose of any vaccine, with the same date in the corresponding unvaccinated individual. The outcome included incident symptomatic Covid-19 infection occurring >14 days after baseline.
FINDINGS RESULTS
During a mean follow-up time of 76 (range 1-183) days, symptomatic Covid-19 infection was confirmed in 187 individuals with heterologous vaccine schedules (incidence rate: 2.0/100,000 person-days) and in 306 individuals from the unvaccinated control group (incidence rate: 7.1/100,000 person-days). The adjusted vaccine effectiveness was 67% (95% CI, 59-73, P<0.001) for heterologous ChAdOx1 nCoV-19 / BNT162b2 prime-boost vaccination, and 79% (95% CI, 62-88, P<0.001) for heterologous ChAdOx1 nCoV-19 / mRNA-1273 prime-boost vaccination. When combined and analysed together, the two heterologous vaccine schedules had an effectiveness of 68% (95% CI, 61-74, P<0.001) which was significantly greater (P
INTERPRETATION CONCLUSIONS
The findings of this study suggest that the use of heterologous ChAdOx1 nCoV-19 and mRNA prime-boost vaccination is an effective alternative to increase population immunity against Covid-19, including against the Delta variant which dominated the confirmed cases during the study period. These findings could have important implications for vaccination strategies and logistics, and consequently in the battle against the Covid-19 pandemic.

Identifiants

pubmed: 34693387
doi: 10.1016/j.lanepe.2021.100249
pii: S2666-7762(21)00235-0
pmc: PMC8520818
doi:

Types de publication

Journal Article

Langues

eng

Pagination

100249

Informations de copyright

© 2021 The Author(s).

Déclaration de conflit d'intérêts

None.

Références

Lancet Respir Med. 2021 Nov;9(11):1255-1265
pubmed: 34391547
BMJ. 2021 Mar 11;372:n699
pubmed: 33707182
N Engl J Med. 2021 Jul 8;385(2):187-189
pubmed: 33951357
JAMA. 2021 Jul 6;326(1):35-45
pubmed: 34037666
BMJ. 2021 Aug 20;374:n1943
pubmed: 34417165
Lancet. 2021 Jul 10;398(10295):121-130
pubmed: 34181880
Lancet. 2021 Sep 4;398(10303):856-869
pubmed: 34370971
Lancet. 2021 May 1;397(10285):1646-1657
pubmed: 33901420
N Engl J Med. 2021 Feb 4;384(5):403-416
pubmed: 33378609
Lancet. 2021 May 29;397(10289):2043-2046
pubmed: 33991480
Lancet. 2021 May 15;397(10287):1819-1829
pubmed: 33964222
Lancet. 2021 Jan 9;397(10269):99-111
pubmed: 33306989
N Engl J Med. 2021 Jun 10;384(23):2187-2201
pubmed: 33882225
Nat Med. 2021 Sep;27(9):1614-1621
pubmed: 34244681
MMWR Morb Mortal Wkly Rep. 2021 Apr 02;70(13):495-500
pubmed: 33793460
N Engl J Med. 2021 Apr 15;384(15):1412-1423
pubmed: 33626250
Lancet Infect Dis. 2021 Sep;21(9):1212-1213
pubmed: 34332707
Eur J Epidemiol. 2021 Mar;36(3):287-298
pubmed: 33704634
BMJ. 2021 May 5;373:n1114
pubmed: 33952445
N Engl J Med. 2021 Sep 9;385(11):1049-1051
pubmed: 34260850
Lancet. 2021 Jul 10;398(10295):94-95
pubmed: 34181881
N Engl J Med. 2020 Dec 31;383(27):2603-2615
pubmed: 33301246
Nat Med. 2021 Sep;27(9):1525-1529
pubmed: 34262158

Auteurs

Peter Nordström (P)

Department of Community Medicine and Rehabilitation, Unit of Geriatric Medicine, Umeå University, Umeå, Sweden (Peter Nordström and Marcel Ballin).

Marcel Ballin (M)

Department of Community Medicine and Rehabilitation, Unit of Geriatric Medicine, Umeå University, Umeå, Sweden (Peter Nordström and Marcel Ballin).
Department of Public Health and Clinical Medicine, Section of Sustainable Health, Umeå University, Umeå, Sweden (Marcel Ballin and Anna Nordström).

Anna Nordström (A)

Department of Public Health and Clinical Medicine, Section of Sustainable Health, Umeå University, Umeå, Sweden (Marcel Ballin and Anna Nordström).
School of Sport Sciences, UiT the Arctic University of Norway, Tromsø, Norway (Anna Nordström).

Classifications MeSH