Effect of mRNA Vaccine Boosters against SARS-CoV-2 Omicron Infection in Qatar
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Abstract
BACKGROUND: Waning of vaccine protection against coronavirus disease 2019 (Covid-19) and the emergence of the omicron (or B.1.1.529) variant of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have led to expedited efforts to scale up booster vaccination. Protection conferred by booster doses of the BNT162b2 (Pfizer-BioNTech) and mRNA-1273 (Moderna) vaccines in Qatar, as compared with protection conferred by the two-dose primary series, is unclear. METHODS: We conducted two matched retrospective cohort studies to assess the effectiveness of booster vaccination, as compared with that of a two-dose primary series alone, against symptomatic SARS-CoV-2 infection and Covid-19-related hospitalization and death during a large wave of omicron infections from December 19, 2021, through January 26, 2022. The association of booster status with infection was estimated with the use of Cox proportional-hazards regression models. RESULTS: In a population of 2,239,193 persons who had received at least two doses of BNT162b2 or mRNA-1273 vaccine, those who had also received a booster were matched with persons who had not received a booster. Among the BNT162b2-vaccinated persons, the cumulative incidence of symptomatic omicron infection was 2.4% (95% confidence interval [CI], 2.3 to 2.5) in the booster cohort and 4.5% (95% CI, 4.3 to 4.6) in the nonbooster cohort after 35 days of follow-up. Booster effectiveness against symptomatic omicron infection, as compared with that of the primary series, was 49.4% (95% CI, 47.1 to 51.6). Booster effectiveness against Covid-19-related hospitalization and death due to omicron infection, as compared with the primary series, was 76.5% (95% CI, 55.9 to 87.5). BNT162b2 booster effectiveness against symptomatic infection with the delta (or B.1.617.2) variant, as compared with the primary series, was 86.1% (95% CI, 67.3 to 94.1). Among the mRNA-1273-vaccinated persons, the cumulative incidence of symptomatic omicron infection was 1.0% (95% CI, 0.9 to 1.2) in the booster cohort and 1.9% (95% CI, 1.8 to 2.1) in the nonbooster cohort after 35 days; booster effectiveness against symptomatic omicron infection, as compared with the primary series, was 47.3% (95% CI, 40.7 to 53.3). Few severe Covid-19 cases were noted in the mRNA-1273-vaccinated cohorts. CONCLUSIONS: The messenger RNA (mRNA) boosters were highly effective against symptomatic delta infection, but they were less effective against symptomatic omicron infection. However, with both variants, mRNA boosters led to strong protection against Covid-19-related hospitalization and death. (Funded by Weill Cornell Medicine-Qatar and others.).
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Numerous studies conducted during the Omicron BA.1 period have reported an increase in VE against infection caused by this variant following a booster dose.
“Still, numerous studies conducted during the Omicron BA.1 period have reported an increase in VE against infection caused by this variant following a booster dose [19,26,32-35].”
From Vaccine effectiveness and duration of protection of COVID-19 mRNA vaccines against Delta and Omicron BA.1 symptomatic and severe COVID-19 outcomes in adults aged 50 years and over in France (2023) · cites this paper as [32]
The Results report higher effectiveness against symptomatic Omicron infection after a booster than after a two-dose primary series. The Methods place the study during the Omicron wave, but the passages identify infections as Omicron rather than specifically BA.1; they therefore do not establish the claim for that subvariant. (LLM, conf=0.85)
Experimental — accuracy not yet measuredPrevious 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.”
From Effects of Previous Infection and Vaccination on Symptomatic Omicron Infections (2022) · cites this paper as [4]
The inclusion and exclusion criteria were implemented to allow immunity to build after vaccination and to reduce several potential biases.
“These inclusion and exclusion criteria were implemented to allow for build-up of immunity after vaccination4,14 and to minimize different types of potential bias, as informed by earlier analyses in the same population.”
From Effects of Previous Infection and Vaccination on Symptomatic Omicron Infections (2022) · cites this paper as [4]
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.”
From Effects of Previous Infection and Vaccination on Symptomatic Omicron Infections (2022) · cites this paper as [4]
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”
From Effects of Previous Infection and Vaccination on Symptomatic Omicron Infections (2022) · cites this paper as [4]
Of 315 random SARS-CoV-2-positive specimens collected between December 19, 2021 and January 22, 2022, 300 (95.2%) were confirmed as Omicron infections and 15 (4.8%) as Delta infections.
“A total of 315 random SARS-CoV-2-positive specimens collected between December 19, 2021 and January 22, 2022 were viral whole-genome sequenced on a Nanopore GridION sequencing device. Of these, 300 (95.2%) were confirmed as Omicron infections and 15 (4.8%) as Delta (B.1.617.2)1 infections2,4,5.”
From Duration of mRNA vaccine protection against SARS-CoV-2 Omicron BA.1 and BA.2 subvariants in Qatar (2022) · cites this paper as [5]
Our recent study of the effectiveness of booster vaccination against any symptomatic Omicron infection, relative to the primary series, used a cohort study design and its results are consistent with results generated in the present study using the test-negative, case-control study design.
“Moreover, our recent study of the effectiveness of booster vaccination against any symptomatic Omicron infection, relative to that of the primary series, used a cohort study design5 and its results are consistent with results generated in the present study using the test-negative, case–control study design.”
From Duration of mRNA vaccine protection against SARS-CoV-2 Omicron BA.1 and BA.2 subvariants in Qatar (2022) · cites this paper as [5]
The large Omicron-wave exponential-growth phase in Qatar started on December 19, 2021 and peaked in mid-January, 2022.
“The large Omicron-wave exponential-growth phase in Qatar started on December 19, 2021 and peaked in mid-January, 20222–5.”
From Duration of mRNA vaccine protection against SARS-CoV-2 Omicron BA.1 and BA.2 subvariants in Qatar (2022) · cites this paper as [5]
A prior study from Qatar determined a booster effectiveness of 76.5% (95% CI, 55.9%-87.5%) against Omicron-related hospitalization and death.
“A prior study from Qatar determined a booster effectiveness of 76.5% (95% CI, 55.9%-87.5%) against Omicron-related hospitalization and death.4”
Population studies from the UK and Qatar have demonstrated that receipt of a third (booster) dose of mRNA COVID-19 vaccine increases protection against Omicron infection and severe disease.
“Population studies from the UK and Qatar have demonstrated that receipt of a third (booster) dose of mRNA COVID-19 vaccine increases protection against Omicron infection and severe disease.4,5”
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References 55 · Cited by 380
Research works printed but not linked: 3
- [31]Austin PC. Using the standardized difference to compare the prevalence of a binary variable between two groups in observational research. Commun Stat Simul Comput 2009; 38: 1228- 1234.
- [32]Kaplan EL, Meier P. Nonparametric estimation from incomplete observations. J Am Stat Assoc 1958; 53: 457- 481.
- [37]Buchan SA, Chung H, Brown KA, et al. Effectiveness of COVID-19 vaccines against omicron or delta infection. January 1, 2022 (https://www.medrxiv.org/content/10.1101/2021.12.30.21268565v1). preprint. PMC9500552 36136332 · DOI
- Authors
- Abu-Raddad, L. J., Chemaitelly, H., Ayoub, H. H., AlMukdad, S., Yassine, H. M., Al-Khatib, H. A., Smatti, M. K., Tang, P., Hasan, M. R., Coyle, P., 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.
- Affiliations
- Cornell University (US)
- Queen's University Belfast (GB)
- From the Infectious Disease Epidemiology Group (L.J.A.-R., H.C., S.A.) and the World Health Organization Collaborating Center for Disease Epidemiology Analytics on HIV/AIDS, Sexually Transmitted Infections, and Viral Hepatitis (L.J.A.-R., H.C., S.A.), Weill Cornell Medicine–Qatar, Cornell University, Qatar Foundation–Education City, the Departments of Public Health (L.J.A.-R., H.F.A.-R.) and Biomedical Science (H.M.Y., H.A.A.-K., M.K.S., G.K.N.), College of Health Sciences, QU Health, the Mathematics Program, Department of Mathematics, Statistics, and Physics, College of Arts and Sciences (H.H.A.), the Biomedical Research Center, QU Health (H.M.Y., H.A.A.-K., M.K.S., P.C., G.K.N.), Qatar University, the Department of Pathology, Sidra Medicine (P.T., M.R.H.), Hamad Medical Corporation (P.C., Z.A.-K., E.A.-K., A.J., A.H.K., A.N.L., R.M.S., A.A.B., A.A.-K.), Primary Health Care Corporation (M.G.A.-K.), and the Ministry of Public Health (H.E.A.-R., M.H.A.-T., R.B.) — all in Doha, Qatar; the Departments of Popu...
- Corresponding author
- Abu-Raddad, Laith J.
- ORCID
- Venue
- New England Journal of Medicine
- Publisher
- Massachusetts Medical Society
- Published
- 2022-05-12
- Volume
- 386
- Issue
- 19
- Pages
- 1804-1816
- ISSN
- 0028-4793 (ISSN-L)
- 1533-4406
- PMC
- PMC8929389
- OpenAlex
- W4220678484
- Cited by
- 380
- References
- 55
- Citations by year
- 2026: 15 · 2025: 28 · 2024: 46 · 2023: 139 · 2022: 152
- FWCI
- 44.61
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- New England Journal of Medicine (publishedVersion, other-oa)
- medRxiv (acceptedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Research Portal (Queen's University Belfast) (submittedVersion, other-oa)
- Qatar University QSpace (Qatar University) (submittedVersion)
- Funders
- Biomedical Research Program and the Biostatistics, Epidemiology, and Biomathematics Research Core, both at Weill Cornell Medicine-Qatar
- Qatar Genome Programme and Qatar University Biomedical Research Center
- 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
- Social Sciences › Health › Vaccine Coverage and Hesitancy
- Keywords
- mRNA vaccine booster, Omicron variant, BNT162b2, mRNA-1273, COVID-19 vaccine effectiveness, waning vaccine protection, symptomatic infection, hospitalization, COVID-19 mortality, Delta variant, Qatar, booster vaccination, matched cohort, SARS-CoV-2
- MeSH terms
- Immunogenicity, Vaccine, COVID-19, SARS-CoV-2, COVID-19 Vaccines, mRNA Vaccines, Vaccine Efficacy, BNT162 Vaccine, 2019-nCoV Vaccine mRNA-1273, Breakthrough Infections, Humans, Immunization, Secondary, Qatar, Retrospective Studies, RNA, Messenger, Vaccines, Synthetic, Cohort Studies
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