A Comparison Study of COVID-19 Outcomes based on Vaccination Status among Hospitalized Patients in Wangaya General Hospital Denpasar, Bali

Background: Background: COVID-19 infections continuously spreading and impact the global health and economic system despite rigorous public health protocols. There is evidence that vaccines may reduce transmission, symptomatic infection, and severity of illness, with 70 - 90% vaccine effectiveness. This report provides a comparative analysis of the severity and mortality of COVID-19 infection between vaccinated and unvaccinated individuals who were hospitalized in Wangaya General Hospital Denpasar, Bali. Method: We conducted a retrospective observational study with a case - control design. The data were collected using secondary data from the medical records that were hospitalized in Wangaya General Hospital Denpasar from the last June 2021 through August 2021. The data that met the inclusion criteria were then analyzed with SPSS 22.0. Result: On bivariate analysis showed there is a significant correlation between vaccination status with outcome of COVID-19 infections (p= 0, 032) and the severity of illness (p= 0, 017). The multivariate analysis was done at the variables that showed significant result in bivariate analysis. The binary logistic regression was done. The result showed that age (p= 0, 045; 95% CI 1, 002 - 1, 209), D - dimer level (p= 0, 006; 95% CI 1, 000 - 1, 001), length of stay (p= 0, 006; 95% CI 0, 386 - 0, 855), and vaccination status (p= 0, 048; 95% CI 1, 025 - 564, 786) significantly correlated with the outcome. While only gender (p= 0, 032; 95% CI 0, 118 - 0, 909) and D - dimer level (p= 0, 001; 95% CI 1, 000 - 1, 001) has strong correlation with severity of illness. However, vaccination had protective effect against severe - critical illness (OR=0.318; p= 0.017) and mortality (OR= 0.20; p=0.032) when infected by SARS - CoV - 2. Conclusion: COVID-19 vaccines play a critical role in this devastating pandemic situation. Vaccinated patients have shown good outcomes when infected by SARS - CoV - 2 compared with unvaccinated patients.