Effectiveness of ChAdOx1 vaccine in older adults during SARS-CoV-2 Gamma variant circulation in São Paulo.
Journal
Nature communications
ISSN: 2041-1723
Titre abrégé: Nat Commun
Pays: England
ID NLM: 101528555
Informations de publication
Date de publication:
28 10 2021
28 10 2021
Historique:
received:
10
09
2021
accepted:
08
10
2021
entrez:
29
10
2021
pubmed:
30
10
2021
medline:
16
11
2021
Statut:
epublish
Résumé
A two-dose regimen of the Oxford-AstraZeneca (ChAdOx1) Covid-19 vaccine with an inter-dose interval of three months has been implemented in many countries with restricted vaccine supply. However, there is limited evidence for the effectiveness of ChAdOx1 by dose in elderly populations in countries with high prevalence of the Gamma variant of SARS-CoV-2. Here, we estimate ChAdOx1 effectiveness by dose against the primary endpoint of RT-PCR-confirmed Covid-19, and secondary endpoints of Covid-19 hospitalization and Covid-19-related death, in adults aged ≥60 years during an epidemic with high Gamma variant prevalence in São Paulo state, Brazil using a matched, test-negative case-control study. Starting 28 days after the first dose, effectiveness of a single dose of ChAdOx1 is 33.4% (95% CI, 26.4-39.7) against Covid-19, 55.1% (95% CI, 46.6-62.2) against hospitalization, and 61.8% (95% CI, 48.9-71.4) against death. Starting 14 days after the second dose, effectiveness of the two-dose schedule is 77.9% (95% CI, 69.2-84.2) against Covid-19, 87.6% (95% CI, 78.2-92.9) against hospitalization, and 93.6% (95% CI, 81.9-97.7) against death. Completion of the ChAdOx1 vaccine schedule affords significantly increased protection over a single dose against mild and severe Covid-19 outcomes in elderly individuals during widespread Gamma variant circulation.
Identifiants
pubmed: 34711813
doi: 10.1038/s41467-021-26459-6
pii: 10.1038/s41467-021-26459-6
pmc: PMC8553924
doi:
Substances chimiques
COVID-19 Vaccines
0
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
6220Subventions
Organisme : NCATS NIH HHS
ID : UL1 TR001863
Pays : United States
Informations de copyright
© 2021. The Author(s).
Références
Nature. 2021 Aug;596(7872):417-422
pubmed: 34192737
Lancet Microbe. 2021 Jul;2(7):e283-e284
pubmed: 33846703
N Engl J Med. 2021 Apr 15;384(15):1412-1423
pubmed: 33626250
BMJ. 2021 Aug 20;374:n1943
pubmed: 34417165
Nat Commun. 2021 Jun 8;12(1):3449
pubmed: 34103510
Lancet Reg Health Am. 2021 Sep;1:100025
pubmed: 34386791
N Engl J Med. 2021 Feb 4;384(5):403-416
pubmed: 33378609
Lancet Microbe. 2021 Oct;2(10):e527-e535
pubmed: 34258603
Clin Infect Dis. 2022 Apr 9;74(7):1158-1165
pubmed: 34244723
BMJ. 2021 May 12;373:n1087
pubmed: 33980718
N Engl J Med. 2021 Aug 12;385(7):585-594
pubmed: 34289274
BMJ. 2021 Aug 20;374:n2015
pubmed: 34417194
BMJ. 2021 May 13;373:n1088
pubmed: 33985964
Lancet Infect Dis. 2021 Nov;21(11):1539-1548
pubmed: 34174190
N Engl J Med. 2021 Jul 8;385(2):179-186
pubmed: 34161052
Epidemiology. 2022 Jul 1;33(4):450-456
pubmed: 35384900
BMJ. 2021 Jan 6;372:n18
pubmed: 33408068
Lancet. 2021 Jan 9;397(10269):99-111
pubmed: 33306989
Am J Epidemiol. 2016 Sep 1;184(5):345-53
pubmed: 27587721
Lancet. 2021 May 1;397(10285):1646-1657
pubmed: 33901420
Science. 2021 May 21;372(6544):815-821
pubmed: 33853970
PLoS Biol. 2021 Apr 21;19(4):e3001211
pubmed: 33882066
Nat Med. 2021 Jul;27(7):1230-1238
pubmed: 34035535
Epidemiology. 2021 Jul 1;32(4):508-517
pubmed: 34001753
Lancet. 2021 Mar 6;397(10277):881-891
pubmed: 33617777
N Engl J Med. 2021 May 20;384(20):1885-1898
pubmed: 33725432
N Engl J Med. 2020 Dec 31;383(27):2603-2615
pubmed: 33301246