Dataset Information

Effectiveness of heterologous COVID-19 vaccine booster dosing in Brazilian healthcare workers, 2021.

ABSTRACT:

Objectives

Little is currently known about vaccine effectiveness (VE) for either two doses of Oxford-AstraZeneca (ChAdOx1) viral vector vaccine or CoronaVac inactivated viral vaccine followed by a third dose of mRNA vaccine (Pfizer/BioNTech) among healthcare workers (HCWs).

Methods

We conducted a retrospective cohort study among HCWs (aged ≥18 years) working in a private healthcare system in Brazil from January to December 2021. VE was defined as 1-IRR (incidence rate ratio), with IRR determined using Poisson models with the occurrence of laboratory-confirmed COVID-19 infection as the outcome, adjusting for age, sex, and job type. We compared those receiving viral vector or inactivated viral primary series (two doses) to those who received an mRNA booster.

Results

A total of 11,427 HCWs met the inclusion criteria. COVID-19 was confirmed in 31.5% of HCWs receiving two doses of CoronaVac vaccine vs. 0.9% of HCWs receiving two doses of CoronaVac vaccine with mRNA booster (p < 0.001), and 9.8% of HCWs receiving two doses of ChAdOx1 vaccine vs. 1% among HCWs receiving two doses of ChAdOx1 vaccine with mRNA booster (p < 0.001). In the adjusted analyses, the estimated VE was 92.0% for two CoronaVac vaccines plus mRNA booster, and 60.2% for two ChAdOx1 vaccines plus mRNA booster, when compared to those with no mRNA booster. Of 246 samples screened for mutations, 191 (77.6%) were Delta variants.

Conclusions

While two doses of ChAdOx1 or CoronaVac vaccines prevent COVID-19, the addition of a Pfizer/BioNTech booster provided significantly more protection.

SUBMITTER: Marra AR

PROVIDER: S-EPMC9213833 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Publications

Effectiveness of Heterologous Coronavirus Disease 2019 (COVID-19) Vaccine Booster Dosing in Brazilian Healthcare Workers, 2021.

Marra Alexandre R AR Miraglia João Luiz JL Malheiros Daniel Tavares DT Guozhang Yang Y Teich Vanessa Damazio VD da Silva Victor Elivane E Rebello Pinho João Renato JR Cypriano Adriana A Vieira Laura Wanderly LW Polonio Miria M Ornelas Rafael Herrera RH de Oliveira Solange Miranda SM Borges Junior Flavio Araujo FA Oler Silvia Cristina Cassiano SCC Schettino Guilherme de Paula Pinto GPP de Oliveira Ketti Gleyzer KG Ferraz Santana Rúbia Anita RA de Mello Malta Fernanda F Amgarten Deyvid D Boechat Ana Laura AL Trecenti Noelly Maria Zimpel NMZ Kobayashi Takaaki T Salinas Jorge L JL Edmond Michael B MB Rizzo Luiz Vicente LV

Clinical infectious diseases : an official publication of the Infectious Diseases Society of America 20230201 3

<h4>Background</h4>Little is currently known about vaccine effectiveness (VE) for either 2 doses of Oxford-AstraZeneca (ChAdOx1) viral vector vaccine or CoronaVac (Instituto Butantan) inactivated viral vaccine followed by a third dose of mRNA vaccine (Pfizer/BioNTech) among healthcare workers (HCWs).<h4>Methods</h4>We conducted a retrospective cohort study among HCWs (aged ≥18 years) working in a private healthcare system in Brazil from January to December 2021. VE was defined as 1 - incidence r ...[more]

PMID: 35639918

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