Cited by 445SARS-CoV-2 and COVID-19 ResearchCOVID-19 epidemiological studiesCOVID-19 Clinical Research Studies

Protection against the Omicron Variant from Previous SARS-CoV-2 Infection

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Altarawneh, Heba N., Chemaitelly, Hiam, Hasan, Mohammad R., Ayoub, Houssein H., Qassim, Suelen, AlMukdad, Sawsan, Coyle, Peter, Yassine, Hadi M. +18 more·2022·New England Journal of Medicine

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Abstract

C o r r e s p o n d e n c e Protection against the Omicron Variant from Previous SARS-CoV-2 InfectionTo the Editor: Natural infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) elicits strong protection against reinfection with the B.1.1.7 (alpha), 1,2 B.1.351(beta), 1 and B.1.617.2 (delta) 3 variants.However, the B.1.1.529(omicron) variant harbors multiple mutations that can mediate immune evasion.We estimated the effectiveness of previous infection in preventing symptomatic new cases caused by omicron and other SARS-CoV-2 variants in Qatar.In this study, we extracted data regarding coronavirus disease 2019 (Covid-19) laboratory testing, vaccination, clinical infection data, and related demographic details from the national SARS-CoV-2 databases, which include all results of polymerase-chain-reaction (PCR) testing, vaccinations, and hospitalizations and deaths for Covid-19 in Qatar since the start of the pandemic.The effectiveness of previous SARS-CoV-2 infection in preventing reinfection was defined as the proportional reduction in susceptibility to infection among persons who had recovered from infection as compared with those who had not been infected.4 Previous SARS-CoV-2 infection was defined as a positive result on PCR assay at least 90 days before a new positive PCR finding.4 We used a test-negative, case-control study design to assess the effectiveness of previ-

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  • Previous infections in the study were considered to be caused by variants other than omicron because they occurred before the omicron wave in Qatar.

    “Accordingly, previous infections in this study were considered to be due to variants other than omicron, since they occurred before the omicron wave in Qatar.”
  • Among 315 random SARS-CoV-2-positive specimens sequenced, 300 (95.2%) were omicron and 15 (4.8%) were delta.

    “Of these specimens, 300 (95.2%) were confirmed to be omicron infections and 15 (4.8%) to be delta (or B.1.617.2)1 infections.”
  • The findings are explained by short-lived protection of primary-series vaccination against omicron and more durable protection from natural infection.

    “These findings are explained by the short-lived protection of primary-series vaccination against omicron infections3,27 and the more durable protection from natural infection,2,28 as confirmed by the additional analysis of protection as a function of time after previous infection or vaccination (Figure 3).”
  • The results confirmed other findings: approximately 50% protection from previous infection against BA.1 reinfection, approximately 50% protection from mRNA boosters compared with primary series, and negligible mRNA vaccine effectiveness against omicron infection six or more months after the second dose.

    “The results confirmed other findings that we reported recently, including a protection of approximately 50% for previous infection against reinfection with BA.1,2 a protection of approximately 50% for mRNA boosters as compared with primary series,4 and the finding that mRNA vaccines have negligible effectiveness against omicron infection 6 or more months after the second dose.3”
  • Extensive sensitivity and additional analyses were conducted to investigate potential bias in earlier studies using similar methods, and these analyses showed consistent findings.

    “Extensive sensitivity and additional analyses were conducted to investigate effects of potential bias in our earlier studies that used similar methods. These included different adjustments and controls in the analysis and different study inclusion and exclusion criteria to investigate whether effectiveness estimates could have been biased.12,22 These analyses showed consistent findings.2,3,12,17,2”

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Authors
Altarawneh, H. N., Chemaitelly, H., Hasan, M. R., Ayoub, H. H., Qassim, S., AlMukdad, S., Coyle, P., Yassine, H. M., Al-Khatib, H. A., Benslimane, F. M., Al-Kanaani, Z., Al-Kuwari, E., Jeremijenko, A., Kaleeckal, A. H., Latif, A. N., Shaik, R. M., Abdul-Rahim, H. F., Nasrallah, G. K., Al-Kuwari, M. G., Butt, A. A., Al-Romaihi, H. E., Al-Thani, M. H., Al-Khal, A., Bertollini, R., Tang, P., & Abu-Raddad, L. J.
Affiliations
  • Weill Cornell Medical College in Qatar (QA)
  • Sidra Medicine, Doha, Qatar
  • Qatar University (QA)
  • Hamad Medical Corporation (QA)
  • Primary Health Care (QA)
  • Ministry of Public Health (QA)
Corresponding author
Abu-Raddad, Laith J.
Venue
New England Journal of Medicine
Published
2022-03-31
Volume
386
Issue
13
Pages
1288-1290
ISSN
  • 0028-4793 (ISSN-L)
  • 1533-4406
OpenAlex
W4211118466
Cited by
445
References
24
Citations by year
2026: 10 · 2025: 32 · 2024: 66 · 2023: 129 · 2022: 208
FWCI
53.43
Type
journal article
Language
en
Open access
Locations
  • New England Journal of Medicine (publishedVersion)
  • medRxiv (acceptedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
  • Qatar University QSpace (Qatar University) (submittedVersion)
Funders
  • Qatar Genome Program and Qatar University Biomedical Research Center
  • Biomedical Research Program and the Biostatistics, Epidemiology, and Biomathematics Research Core at Weill Cornell Medicine–Qatar
  • Qatar Ministry of Public Health; Hamad Medical Corporation; and Sidra Medicine
Topics
  • Health Sciences › Medicine › Infectious Diseases › SARS-CoV-2 and COVID-19 Research
  • Physical Sciences › Mathematics › Modeling and Simulation › COVID-19 epidemiological studies
  • Health Sciences › Medicine › Infectious Diseases › COVID-19 Clinical Research Studies
Keywords
Omicron variant, SARS-CoV-2, natural immunity, prior infection, reinfection prevention, immune evasion, symptomatic COVID-19, test-negative design, Qatar
MeSH terms
COVID-19, SARS-CoV-2, Humans, Adaptive Immunity

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