Demographic Features of COVID-19 in Two Waves in A Single Center

Authors : Rishav MUKHERJEE, Dharitri CHAUDHURİ, Arup Kumar MİTRA, Partha GUCHHAİT, Subhrojyoti BHOWMİK, Satadal DAS, Bhaskar Narayan CHAUDHURİ

Pages : 174-182

Doi:10.5799/jmid.1036705

View : 9 | Download : 3

Publication Date : 2021-12-15

Article Type : Research Paper

Abstract :Objectives: This study was undertaken to understand commonly affected age groups, the prevalence of asymptomatic cases, and vaccine efficacy in Kolkata-centric COVID-19 patients. Methods: A retrospective analysis of COVID-19 patients’ data from May 2020 to July 2021 from Peerless Hospitex Hospital & Research Center Ltd., a tertiary care private hospital of Kolkata, West Bengal, was done. Results: A total of 67,121 samples were tested for COVID-19 between May 2020 and July 2021, with the COVID-19 positivity rate of 23.8 % noted over this period. A direct correlation was found between the number of tests conducted and the positivity. The first wave of the pandemic was observed to be from May to December 2020, while the second wave began from April 2021 and declined by July 2021. This correlated with the first and second waves observed in India. The first wave mainly affected the elderly population, while the second wave more affected the younger and middle-aged population. The percentage of asymptomatic patients increased during the second wave compared to the first wave. By comparing the percentage of vaccinated individuals who tested COVID-19 positive following Covaxin vs. Covishield vaccination, although after the first dose, Covishield was observed to be more effective than Covaxin, after the second dose, efficacies of Covaxin and Covishield were not found to differ significantly. Conclusion: The pattern of COVID-19 cases in Kolkata is similar to the National pattern; however, in the second wave, younger and middle-aged persons, females, and asymptomatic cases were significantly more than the first wave. J Microbiol Infect Dis 2021; 11insert ignore into journalissuearticles values(4);:174-182.
Keywords : COVID 19, demography, vaccine efficacy