ABSTRACT
The presented work contains an analysis of seroprevalence, tension, and duration of post-vaccination immunity to the SARS-CoV-2 coronavirus in the residents of the Republic of Belarus after immunization with two vaccine preparations available in the country: Sputnik V and Vero Cell. It was found that seroconversion after the injection of the Vero Cell vaccine occurred significantly later than after the Sputnik V vaccine (p < 0.001). Nevertheless, two-stage immunization with the vaccines provided a sufficiently high efficiency of the inoculated antibodies to the S protein of the COVID-19 pathogen: the proportion of seropositive persons reached 99.19 [96.89;99.97] % for Sputnik V and 96.03 [90.81;98.53] % for Vero Cell. The efficiency of antibody formation after immunization with the Vero Cell vaccine was lower in older persons (in the group > 65 years). The proportion of individuals with the highest IgG score for the SARS-CoV-2 S protein was higher after the Sputnik V administration compared to that in response to the Vero Cell vaccine (p < 0.05), and gradually decreased over time. However, no significant decrease in the level of seropositive individuals after 90 days from the start of immunization with the both vaccine preparations was detected. In COVID-19 survivors immunized with the Sputnik V vaccine, the quantitative indicators of post-vaccination antibodies reached their peak values after 1 dose of the vaccine. The obtained results complement the accumulated world science and practical information on the problem of the post-vaccination immunity formation in the context of the use of different drugs against COVID-19.