Efficacy of corona virus disease 2019 vaccines on oxygen demand, intensive care unit administration and mortality: a single centre retrospective study

Abstract

<b>Aims and objectives:</b> The recent corona virus disease 2019 (COVID-19) pandemic produced high and excessive demands for hospitalization. Vaccination is an efficient strategy to reduce hospitalization and intensive care unit (ICU) admission. With this study our aim is to present efficacy of vaccination on oxygen demand, ICU admission and mortality rate. <b>Methods:</b> In this retrospective study, we surveyed COVID-19 positive patients hospitalised from October 2021 to January 2022, in North Cyprus. Among these 189 patients 93 needed supplemental oxygen therapy. These patients were divided into subgroups according to their vaccination status, and the vaccinated patients were further classified under vaccine types and booster numbers. <b>Results:</b> Of the 93 patients, 40% (n=38) experienced severe symptoms leading to ICU admission and their mortality rate is 15% (n=14). ICU admission and mortality rate is found to be 38% (n=20) and 19% (n=10) respectively in the unvaccinated group (n=52). 41 vaccinated patients were admitted to the ICU. 44%(n=8) were injected with booster, 22% (n=4) with inactive vaccine, 22%(n=4), with mRNA and 11% (n=2) with vector vaccine. Mortality rate among vaccinated patients is 9.8%(n=4). <b>Conclusions:</b> The study have shown that there is no difference between the mortality rates (p=0.52) of vaccinated and unvaccinated patients who needed supplementary oxygen therapy.&nbsp;Their ICU admission rate (p=0.67) does not show a significant difference as well. The results demonstrate that even though ICU admission does not differ in vaccinated and unvaccinated groups, mortality rate is double in the latter (p=0.25).