lancet-header

Preprints with The Lancet is part of SSRN´s First Look, a place where journals identify content of interest prior to publication. Authors have opted in at submission to The Lancet family of journals to post their preprints on Preprints with The Lancet. The usual SSRN checks and a Lancet-specific check for appropriateness and transparency have been applied. Preprints available here are not Lancet publications or necessarily under review with a Lancet journal. These preprints are early stage research papers that have not been peer-reviewed. The findings should not be used for clinical or public health decision making and should not be presented to a lay audience without highlighting that they are preliminary and have not been peer-reviewed. For more information on this collaboration, see the comments published in The Lancet about the trial period, and our decision to make this a permanent offering, or visit The Lancet´s FAQ page, and for any feedback please contact preprints@lancet.com.

Effectiveness of the Bivalent mRNA Vaccine in Preventing Severe COVID-19 Outcomes: An Observational Cohort Study

17 Pages Posted: 3 Jan 2023

See all articles by Ronen Arbel

Ronen Arbel

Clalit Health Services - Community Medical Services Division

Alon Peretz

Clalit Health Services - Community Medical Services Division

Ruslan Sergienko

Ben-Gurion University of the Negev - Faculty of Health Science

Michael Friger

Ben-Gurion University of the Negev - Faculty of Health Science

Tanya Beckenstein

Clalit Health Services - Community Medical Services Division

Shlomit Yaron

Clalit Health Services - Community Medical Services Division

Ariel Hammerman

Clalit Health Services - Community Medical Services Division

Natalya Bilenko

Ben-Gurion University of the Negev - Faculty of Health Science

Doron Netzer

Clalit Health Services - Community Medical Services Division

More...

Abstract

Background: During Late 2022, the SARS-CoV-2 Omicron BA.5 sublineages accounted for most of the sequenced viral genomes worldwide. Bivalent mRNA vaccines contain an ancestral SARS-CoV-2 strain component plus an updated component of the Omicron BA.4/BA.5. Since September 2022, a single bivalent booster dose has been recommended for adults who have completed a primary vaccination series and are at high risk for severe Covid-19 disease. Evidence regarding the effectiveness of the bivalent vaccine in reducing hospitalizations and death due to Covid-19 is warranted.

Methods: This retrospective cohort study included all members of Clalit Health Services, aged ≥65, eligible for a bivalent booster. Hospitalizations and death due to Covid-19 among participants who received the bivalent vaccine were compared with those who did not. A Cox proportional-hazards regression model with time-dependent covariates was used to estimate the association between the bivalent vaccine and Covid-19 outcomes while adjusting for demographic factors and coexisting illnesses.

Findings: A total of 622,701 participants met the eligibility criteria. Of those, 85,314 (14%) received a bivalent-booster during the 70-day study period. Hospitalization due to Covid-19 occurred in 6 bivalent recipients and 297 participants who did not, adjusted hazard ratio (HR): 0.19 (95% CI, 0.08-0.43). Death due to Covid-19 occurred in 1 bivalent recipient and 73 participants who did not, adjusted HR 0.14: (95% CI, 0.02-1.04).

Interpretation: Participants who received the bivalent vaccine had lower hospitalization and mortality rates due to Covid-19 than non-recipients up to 70 days after vaccination.
Funding Information: None.

Declaration of Interests: All authors report no conflict of interest.

Ethics Approval Statement: The CHS Institutional Helsinki and Data Utilization Committees approved the study.

Keywords: COVID-19, Bivalent booster vaccine

Suggested Citation

Arbel, Ronen and Peretz, Alon and Sergienko, Ruslan and Friger, Michael and Beckenstein, Tanya and Yaron, Shlomit and Hammerman, Ariel and Bilenko, Natalya and Netzer, Doron, Effectiveness of the Bivalent mRNA Vaccine in Preventing Severe COVID-19 Outcomes: An Observational Cohort Study. Available at SSRN: https://ssrn.com/abstract=4314067 or http://dx.doi.org/10.2139/ssrn.4314067

Ronen Arbel (Contact Author)

Clalit Health Services - Community Medical Services Division ( email )

Tel Aviv
Israel

Alon Peretz

Clalit Health Services - Community Medical Services Division ( email )

Tel Aviv
Israel

Ruslan Sergienko

Ben-Gurion University of the Negev - Faculty of Health Science ( email )

Michael Friger

Ben-Gurion University of the Negev - Faculty of Health Science ( email )

Tanya Beckenstein

Clalit Health Services - Community Medical Services Division ( email )

Shlomit Yaron

Clalit Health Services - Community Medical Services Division ( email )

Tel Aviv
Israel

Ariel Hammerman

Clalit Health Services - Community Medical Services Division ( email )

Natalya Bilenko

Ben-Gurion University of the Negev - Faculty of Health Science ( email )

Doron Netzer

Clalit Health Services - Community Medical Services Division ( email )

Tel Aviv
Israel

Click here to go to TheLancet.com

Paper statistics

Downloads
5,555
Abstract Views
31,850
PlumX Metrics