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. 2023 Feb 8;76(3):e469-e476.
doi: 10.1093/cid/ciac380.

Reduced Odds of Severe Acute Respiratory Syndrome Coronavirus 2 Reinfection After Vaccination Among New York City Adults, July 2021-November 2021

Alison Levin-Rector  1 , Lauren Firestein  1 , Emily McGibbon  1 , Jessica Sell  1 , Sungwoo Lim  2 , Ellen H Lee  1 , Don Weiss  1 , Anita Geevarughese  3 , Jane R Zucker  4   5 , Sharon K Greene  1
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Reduced Odds of Severe Acute Respiratory Syndrome Coronavirus 2 Reinfection After Vaccination Among New York City Adults, July 2021-November 2021

Alison Levin-Rector et al. Clin Infect Dis. .

Abstract

Background: Belief that vaccination is not needed for individuals with prior infection contributes to coronavirus disease 2019 (COVID-19) vaccine hesitancy. Among individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) before vaccines became available, we determined whether vaccinated individuals had reduced odds of reinfection.

Methods: We conducted a case-control study among adult New York City residents who tested positive for SARS-CoV-2 infection in 2020 and had not died or tested positive again >90 days after an initial positive test as of 1 July 2021. Case patients with reinfection during July 2021-November 2021 and controls with no reinfection were matched (1:3) on age, sex, timing of initial positive test in 2020, and neighborhood poverty level. Matched odds ratios (mORs) and 95% confidence intervals (CIs) were calculated using conditional logistic regression.

Results: Of 349 827 eligible adults, 2583 were reinfected during July 2021-November 2021. Of 2401 with complete matching criteria data, 1102 (45.9%) were known to be symptomatic for COVID-19-like illness, and 96 (4.0%) were hospitalized. Unvaccinated individuals, compared with individuals fully vaccinated within the prior 90 days, had elevated odds of reinfection (mOR, 3.21; 95% CI, 2.70 to 3.82), of symptomatic reinfection (mOR, 2.97; 95% CI, 2.31 to 3.83), and of reinfection with hospitalization (mOR, 2.09; 95% CI, .91 to 4.79).

Conclusions: Vaccination reduced odds of reinfections when the Delta variant predominated. Further studies should assess risk of severe outcomes among reinfected persons as new variants emerge, infection- and vaccine-induced immunity wanes, and booster doses are administered.

Keywords: COVID-19; Delta variant; SARS-CoV-2; reinfection; vaccination.

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Conflict of interest statement

Potential conflicts of interest. The authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.

Figures

Graphical Abstract
Graphical Abstract
Figure 1.
Figure 1.
Eligibility for analysis of COVID-19 vaccination status and SARS-CoV-2 reinfection during July 2021–November 2021 among New York City residents with first SARS-CoV-2 infection in 2020. Abbreviations: COVID-19, coronavirus disease 2019; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.
See this image and copyright information in PMC

References

    1. Thompson CN, Baumgartner J, Pichardo C, et al. . COVID-19 outbreak—New York City, February 29–June 1, 2020. MMWR Morb Mortal Wkly Rep 2020; 69:1725–9. - PMC - PubMed
    1. New York City Department of Health and Mental Hygiene . COVID-19: data. Available at:https://www1.nyc.gov/site/doh/covid/covid-19-data.page. Accessed 19 October 2021.
    1. New York City Department of Health and Mental Hygiene . 2020 Advisory #8: COVID-19 update for New York City. Available at:https://www1.nyc.gov/assets/doh/downloads/pdf/han/advisory/2020/covid-19.... Accessed 18 October 2021.
    1. New York State Governor’s Office . Video, audio, photos & rush transcript: Governor Cuomo announces first dose of COVID-19 vaccine administered in United States. Available at:https://www.governor.ny.gov/news/video-audio-photos-rush-transcript-gove.... Accessed 28 September 2021.
    1. Scobie HM, Johnson AG, Suthar AB, et al. . Monitoring incidence of COVID-19 cases, hospitalizations, and deaths, by vaccination status—13 U.S. Jurisdictions, April 4-July 17, 2021. MMWR Morb Mortal Wkly Rep 2021; 70:1284–90. - PMC - PubMed

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