Cited by 170SARS-CoV-2 and COVID-19 ResearchVaccine Coverage and HesitancyCOVID-19 epidemiological studies

Elapsed time since BNT162b2 vaccine and risk of SARS-CoV-2 infection: test negative design study

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Israel, Ariel, Merzon, Eugene, Schäffer, Alejandro A, Shenhar, Yotam, Green, Ilan, Golan-Cohen, Avivit, Ruppin, Eytan, Magen, Eli +1 more·2021·BMJ

Published version of a preprint

Abstract

Objectives: To determine whether time elapsed since the second injection of the Pfizer-BioNTech BNT162b2 mRNA vaccine was significantly associated with the risk of covid-19 infection after vaccination in people who received two vaccine injections. Design: Test negative design study. Setting: Electronic health records of a large state mandated healthcare organisation, Israel. Participants: Adults aged ≥18 years who had received a reverse transcription polymerase chain reaction (RT-PCR) test between 15 May 2021 and 17 September 2021, at least three weeks after their second vaccine injection, had not received a third vaccine injection, and had no history of covid-19 infection. Main outcome measures: Positive result for the RT-PCR test. Individuals who tested positive for SARS-CoV-2 and controls were matched for week of testing, age category, and demographic group (ultra-orthodox Jews, individuals of Arab ancestry, and the general population). Conditional logistic regression was adjusted for age, sex, socioeconomic status, and comorbid conditions. Results: 83 057 adults received an RT-PCR test for SARS-CoV-2 during the study period and 9.6% had a positive result. Time elapsed since the vaccine injection was significantly longer in individuals who tested positive (P<0.001). Adjusted odds ratio for infection at time intervals >90 days since vaccination were significantly increased compared with the reference of <90 days: 2.37 (95% confidence interval 1.67 to 3.36) for 90-119 days, 2.66 (1.94 to 3.66) for 120-149 days, 2.82 (2.07 to 3.84) for 150-179 days, and 2.82 (2.07 to 3.85) for ≥180 days (P<0.001 for each 30 day interval). Conclusions: In this large population of adults tested for SARS-CoV-2 by RT-PCR after two doses of mRNA BNT162b2 vaccine, a gradual increase in the risk of infection was seen for individuals who received their second vaccine dose after at least 90 days.

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Authors
Israel, A., Merzon, E., Schäffer, A. A., Shenhar, Y., Green, I., Golan-Cohen, A., Ruppin, E., Magen, E., & Vinker, S.
Affiliations
  • Leumit Health Services, Tel Aviv, Israel
  • Tel Aviv University (IL)
  • National Institutes of Health (US)
  • Ben-Gurion University of the Negev (IL)
Corresponding author
Israel, Ariel
Venue
BMJ
Publisher
BMJ
Published
2021-11-24
Volume
375
Pages
e067873
ISSN
1756-1833 (ISSN-L)
OpenAlex
W3216422624
Cited by
170
References
24
Citations by year
2026: 5 · 2025: 13 · 2024: 19 · 2023: 30 · 2022: 73 · 2021: 30
FWCI
12.04
Type
journal article
Language
en
Open access
Locations
  • BMJ (publishedVersion, cc-by-nc)
  • medRxiv (acceptedVersion, cc-by-nc-nd)
  • PubMed Central (publishedVersion, cc-by-nc)
  • PubMed (publishedVersion)
  • PubMed Central (submittedVersion, cc-by-nc-nd)
Funders
  • U.S. Department of Health and Human Services
  • National Institutes of Health
  • National Cancer Institute
Topics
  • Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
  • Social Sciences › Health › Vaccine Coverage and Hesitancy
  • Physical Sciences › Mathematics › Modeling and Simulation › COVID-19 epidemiological studies
Keywords
BNT162b2, mRNA vaccines, COVID-19 pandemic, waning vaccine effectiveness, breakthrough infection, vaccine protection duration, ultra-Orthodox Jews, Arab ancestry, Israel

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