Assessment of humoral immunity to SARS-CoV-2 among employees of medical organizations in the Republic of Tatarstan

Abstract

BACKGROUND: Since the beginning of the pandemic of a new coronavirus infection, preventive measures aimed at combating the spread of the pathogen, preventing the development of severe forms of infection and deaths have been improved. Despite the absence of a legally established generally accepted post-vaccination protective value of antibodies to coronavirus, the study of the presence of antibodies and the determination of their amount in the blood serum of the vaccinated population continues.
 AIM: The aim of the study is to present the results of the study of humoral immunity to SARS COV-2 in medical organizations.
 MATERIALS AND METHODS: The study involved employees of medical organizations of the State Autonomous Health Institution "Republican Clinical Dermatovenerologic Dispensary of the Ministry of Health of the Republic of Tatarstan named after Professor A.G. Ge" in Kazan and the State Autonomous Health Institution "City Polyclinic No. 3" in Naberezhnye Chelny in the number of 393 people who were vaccinated with the two-component vaccine GamCovidVac (Sputnik V), after which a sufficient amount of time has passed for the formation of an immune response: more than 21 days. The blood sera of 393 people (including 350 women) were examined for the determination of specific IgG to SARS-CoV-2 by enzyme immunoassay using the Vector-Best kit (Novosibirsk, Russia). Statistical analysis was carried out using the StatTech v. 2.8.8 (developer - Stattech LLC, Russia).
 RESULTS:
 The median of the age of the subjects was 47 years (Q1 - Q3:39-59). The mean antibody titer level was 570 BAU/ml (Q1 Q3:128-1150). A correlation analysis of the relationship between titer levels and age at the time of vaccination was performed, according to the results of which a weak direct relationship was established, and when assessing the dependence of antibody titer levels on the duration of vaccination after the second component at the time of checking the titers, there was no connection.
 CONCLUSIONS:
 The ongoing pandemic of a new coronavirus infection with the emergence of new forms of the disease caused by other strains of the virus, the improvement of prevention methods, requires constant monitoring of the epidemiological situation with the study of the effectiveness of vaccines, including at the cellular level.