CT severity score: an imaging biomarker to estimate the severity of COVID-19 pneumonia in vaccinated and non-vaccinated population

Abstract

BackgroundIn India, two vaccines received emergent use authorization, namely Covishield (a brand of the Oxford—Astra Zeneca vaccine manufactured by the Serum institute of India) and Covaxin (developed by Bharat Biotech) against COVID-19 disease. Chest CT is an objective way to assess the extent of pulmonary parenchymal involvement. This study aims to estimate the disease severity and outcome due to COVID-19 among vaccinated and non-vaccinated symptomatic patients and compare the same in Covishield versus Covaxin recipients using CT severity score.ResultsA total of 306 patients were retrospectively evaluated. The mean age was 62.56 ± 8.9 years, and males [n-208 (67.97%)] were commonly affected. Of 306 patients, 143 were non-vaccinated (47%), 124 were partially vaccinated (40%), and 39 were completely vaccinated (13%). CT severity scores were reduced in both Covishield and Covaxin recipients in comparison with the non-vaccinated group [χ2 (2) = 16.32, p < 0.001]. There is a reduction in LOS among the vaccinated group, predominantly among the Covishield recipients.ConclusionVaccination confers protection from severe SARS-CoV2 infection and is associated with an overall reduction in mortality.