Is the Omicron Variant of Coronavirus-19 Infection Really Innocent?
Abstract
Background: The Omicron variant of SARS-CoV-2 exhibits higher transmissibility compared to previous variants. This retrospective, single-center study aimed to evaluate the relationship between vaccination status and mortality among patients infected with the Omicron variant.
Methods: This retrospective analysis included 584 patients diagnosed with the Omicron variant of SARS-CoV-2 between January and March 2022 at Bozyaka Training and Research Hospital, Türkiye. Demographic characteristics, comorbidities, laboratory findings, computed tomography (CT) severity scores, vaccination status, and mortality outcomes were assessed. Multivariate logistic regression was used to adjust for potential confounding factors, including age, sex, and comorbidities.
Results: Among the 584 patients, 280 were unvaccinated and 304 vaccinated. Mortality was 21% in unvaccinated patients (mean age 56±17) and 10% in vaccinated patients (mean age 62±15). After adjustment for age and Charlson Comorbidity Index, vaccination remained independently associated with reduced mortality (p<0.05). Unvaccinated patients demonstrated higher inflammatory markers, elevated CT severity scores, and greater ICU admission rates (34% vs. 16%).
Conclusion: Vaccination significantly reduced mortality and lung involvement among patients infected with the Omicron variant. Despite reports of milder disease, Omicron remains clinically significant, particularly in unvaccinated individuals.
Keywords
COVID-19, Mortality, Omicron, SARS-CoV-2, Vaccination
Ethical Statement
This study was conducted at Bozyaka Training and Research Hospital and was approved by the ethics committee (approval number 180, dated 27/10/2021).
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