Measuring the Impact of Single Dose of ChAdOx1 nCOV-19 Corona Virus Vaccine (Recombinant) on Hospital Stay, ICU Requirement, and Mortality Outcome in a Tertiary Care Centre”

Background: Control of the global COVID-19 pandemic will require mass vaccination especially in developing countries. To comparatively evaluate ICU requirement, length of stay and mortality between single dose vaccinated and non-vaccinated hospitalized COVID-19 patients. Methods: Retrospective, observational study from 1st April 2021 till 30th June 2021 carried out in a tertiary care hospital in Western Indian region. Single centre population-based study at a tertiary COVID care centre. 569 patients admitted with positive polymerase chain reaction tests for COVID-19 at our institute were enrolled in the study. 137 admitted patients with single dose of ChAdOx1 nCoV-19 vaccine were considered as Vaccinated patients as per case definition and 432 patients who have not received any dose of vaccine were considered as Non-vaccinated patients. Findings: Main outcomes were length of hospital stay including ward and ICU in both groups. Severity of SARS-CoV-2 infection was determined based on ventilator support and mortality. Of the 569 patients enrolled in the study based on the eligibility criteria, 137 (24.08%) patients had received a single dose of ChAdOx1 nCoV-19 vaccine while 432 (75.92%) patients had not received any form of vaccination. Overall length of stay in the hospital was similar for both groups however a significant difference was seen in length of stay in ward and ICU. Vaccinated patients were admitted for 6.21 ± 3.204 days in the ward while non-vaccinated patients were admitted for 5.56 ± 4.55 days (p<0.001). ICU stay of the 21 vaccinated patients was a mean length of 4.47 ± 2.3 days while for the 145 non-vaccinated patients was 6.29 ± 2.19 days (p<0.001). Mortality was observed in 4 patients in the vaccinated group and 95 patients in the non-vaccinated group. Interpretation:  In this retrospective cohort study of hospitalized patients, a single dose of ChAdOx1 nCoV-19 vaccination compared with no vaccination was associated with a significantly lower severity of SARS-CoV-2 infection. Funding: None to declare. Declaration of Interest: None to declare. Ethical Approval: This study was approved by the KD Hospital Institutional Ethics Committee.