A multicentric study to correlate severity of disease and vaccine in COVID-19 pandemic

Background: The purpose of the study was to find out correlation between severity of disease and vaccine in COVID-19 pandemic. Primary objective was to know occurrence of post-vaccination breakthrough infections in hospitalized patients and secondary objective was to know of COVID-19 vaccine to prevent severe infection, morbidity, and mortality of patients. This retrospective observational multicentric study included 325 confirmed COVID-19 patients on NRBM/BIPAP/ventilator admitted in high dependency unit (HDU)/intensive care unit (ICU) were divided into based on severity of symptoms and vaccination status. We included adult patients having positive RTPCR (reverse transcription polymerase chain reaction) COVID-19 test/high-resolution computed tomography scan (HRCT) thorax suggestive of COVID-19 pneumonia. Patients who developed adverse reaction post-vaccination, pregnant patient, and lactating mother were excluded from the study. Results: Total 325 confirmed COVID-19-positive patients were studied. Statistical analysis with SPSS version 26 and data were analyzed by chi-square test and P value < 0.05 were considered as significant. Total duration of hospital stay was less in vaccinated patients compared to non-vaccinated patients. Oxygen requirement was also less in vaccinated patients. Vaccinated patients developed less severe infection than non-vaccinated patients. Conclusions: COVID-19 vaccination is very effective against severity of disease. It reduces hospitalization, oxygen requirement, and mortality.