The epidemic process of a new coronavirus infection among medical workers in the context of V.D. Belyakov’s theory of self-regulation of parasitic systems
Authors: Sisin Evgeniy I. , Golubkova Alla  A. , Kozlova Irina I. , Ostapenko Nadezhda A. , Ezhova Olga A. , Marapov Damir I. , Platonova Tatyana A. 
Published: March 2023

BACKGROUND: The epidemic process of COVID-19, during the analyzed time interval (20202022), like any parasitic system, had a cyclic course, which corresponded to the main provisions of the theory of V.D. Belyakov on the self-regulation of parasitic systems. At the same time, cyclic changes in the clinical and epidemiological characteristics of the infection occurred in the general population and among its cohorts, including employees of medical organizations. The study of the clinical and epidemiological features of COVID-19 in medical workers at various stages of the pandemic is an important area of scientific research that allows the quick adjustment of preventive and antiepidemic measures for reducing the impact of biological factors on the epidemic process.
AIM: This study determines the clinical and epidemiological features of COVID-19 in medical workers, considering the phase transformations of the pathogen, and assesses the effectiveness of individual antiepidemic measures at different stages of the pandemic.
MATERIALS AND METHODS: The reporting forms General information about patients with positive COVID-19, General information about patients with community-acquired pneumonia with positive COVID-19 (497 units of information), 2176 cards of epidemiological investigation of COVID-19 cases among employees of 3 municipalities were analyzed. Epidemiological and statistical research methods were used.
RESULTS: When studying the epidemic process of a new coronavirus infection among medical workers, there was a decrease in the incidence of COVID-19 and the proportion of severe clinical forms of infection and foci during the pathogen reservation phase that corresponded to the appearance of a new genetic variant. During the epidemic spread phase of the pathogen, the largest number of recurrent disease cases was recorded, and disease cases were among those previously vaccinated against this infection. The coefficient and index of focality and the average duration of the existence of the focus in this phase were higher than in the previous one. Among the factors that negatively affected the epidemic were shortcomings in implementing antiepidemic measures, violations in the flow of technological processes, crowding, and lack of working space. As the number of vaccinated and recovered COVID-19 medical workers increased, the nature of the clinical manifestations of the infection changed regarding an increase in the proportion of mild (erased) forms, and a number of characteristics of the epidemic process also changed regarding the frequency of foci formation with multiple diseases.
CONCLUSIONS: The conducted analytical epidemiological study confirms the universal nature of the main provisions of the theory of V.D. Belyakov about the self-regulation of parasitic systems at the population level. It also allows us to explain the individual characteristics of the epidemic process among specific cohorts, in particular medical workers, considering the phasic nature of the epidemic, the influence of pathogen and host population transformations, and social and natural factors.