The incidence and in-hospital mortality of COVID-19 patients post-vaccination in eastern India

Abstract Objectives: The comparable effectiveness of Covishield and Covaxin vaccines has not been studied. We compared the effectiveness of Covishield and Covaxin vaccines against moderate to severe COVID-19. Methods: In this retrospective observational study, we collected data of patients who were admitted with moderate to severe COVID-19. The vaccination status and comorbidities of the patients were documented. The incidence and in-hospital mortality of COVID-19 patients was assessed. Univariate analysis was performed to determine the risk factors of in-hospital mortality. Results: Of 294 patients, 5.1% (n=15) received Covaxin and 26.5% (n=78) received Covishield; 68.4% (n=201) patients were unvaccinated. Of patients who were vaccinated and contracted COVID-19, 24.8% (n=73) had taken the first dose and 6.8% (n=20) had taken the second dose of either vaccine. The in-hospital mortality rate was 13.6% (n=40). No significant association was found with the type of vaccine and the in-hospital mortality (p=0.23). Significant associations with in-hospital mortality were found with the interval before COVID-19 disease and vaccination (OR, 3.02; p=0.01); and the presence of diabetes mellitus (OR, 2.13; p=0.02), cardiovascular diseases (OR, 2.11; p<0.001), and malignancy (OR: 2.33; p=0.0325). Conclusion: There was no significant difference in the effectiveness of Covaxin and Covishield in terms of the incidence of COVID-19 and in-hospital mortality. Diabetes mellitus, cardiovascular diseases, and malignancies had a significant association with in-hospital mortality in patients with moderate to severe COVID-19.