CLUSTERING OF COVID-19 VACCINES BY SARS-CoV-2 INFECTION LEVEL AFTER TWO VACCINATIONS

Abstract

Vaccination against COVID-19 is designed to provide herd immunity. However, there are cases of SARS-CoV-2 infection after vaccination. Using Python software, we calculated the number of SARS-CoV-2 infections per 100,000 adults after the first and second vaccinations as at July 23, 2021, conducted in St. Petersburg, Russian Federation. After the first vaccination with Gam-COVID-Vac (Sputnik V) vaccine, 544 infections were determined, and after the second vaccination -1,643 cases. After the first vaccination with the EpiVacCorona vaccine, 1,600 infections were calculated, and after the second vaccination -6,073 cases. After the first vaccination with CoviVac vaccine, 1,162 infections were determined, and after the second vaccination -886 cases. Cluster analysis revealed the similarity of epidemiological indicators due to Gam-COVID-Vac and CoviVac vaccines, with EpiVacCorona vaccine isolated in a separate cluster, which is associated with significant differences in the calculated epidemiological parameters.