Dynamics and gender and age features of the COVID-19 EPIDEMIC process in Moscow (results of screening survey for 1.5 years)
Introduction. The increase in the incidence of COVID-19 continues. In the Russian Federation, as of mid-November, the number of cases exceeded 9 million. To this day, the main method for diagnosing COVID-19 is the real-time reverse transcription polymerase chain reaction (RT-PCR) method. At the same time, in order to improve the diagnosis of a new coronavirus infection, a serological examination of patients for the presence of IgM and IgG antibodies has been proposed. Comprehensive epidemiological analysis based on the results of molecular and serological screening is essential to assess the development and course of COVID-19 in order to the necessary measures to prevent new coronavirus infection. Purpose of the study. To assess the dynamics of the epidemiological process of COVID-19 based on the results of SARS-CoV-2 RNA screening and IgM and IgG antibodies to the new coronavirus measurements. Material and methods. All samples were delivered from outpatient clinics and hospitals in Moscow of various profiles, from patients having various types of pathology, including those not related to COVID-19. A total of 2 946 157 smears of patients were examined by the PCT-RT method, and 728 107 blood samples were examined by the IHLA method. Results. Despite the fact that women were examined 18.6% more often than men, the detectability of SARS-CoV-2 RNA is higher in men (17.4% in men versus 15.7% in women). The wave-like nature of COVID-19 detection with a seasonal prevalence, confirmed by serological testing, has been established. Throughout the screening period, an increase in the number of patients with high IgG titers was found. The same we observed with increasing age: the older the age, the greater is the number of patients with high IgG titers. Conclusion. The increase in the prevalence of COVID-19 is seasonal, with elder people at higher risk of infection. The level of herd immunity by the moment of October 2021 is 52.1%. An increase in the vaccination rate will contribute to a faster achievement of the required level.