Age-Specific Dynamics of Risks of COVID-19 of Different Severity among Healthcare and Industrial Workers

Abstract

Introduction: The relevance of the issue of human age-specific vulnerability to effects of environmental factors, especially biological agents, including viral infections, for public health is attributed to the aging of the population and the requirements for considering individual characteristics for a more accurate risk assessment. Objective: To establish age-specific patterns of the COVID-19 risk among healthcare and industrial workers. Materials and methods: We have analyzed the incidence and course of COVID-19 among 729 healthcare workers and 880 industrial workers in 2021–2022. The risk of mild, moderate and severe course of COVID-19 was determined in each age group. The age-specific dynamics of the COVID-19 risk was characterized by its change per year of age of the employees. Results: We established that the incidence of COVID-19 among healthcare workers was 1.6 times higher than among industrial workers. We also observed regularities of the age-specific dynamics of risk of COVID-19 of different severity among healthcare and industrial workers. For the mild course of the disease, the risk was approximated by the following regressions: healthcare Ri 1 (%) = –0.15 × (Age – 20, years) + 34.06; industry Ri 1 (%) = –0.24 × (Age – 20) + 27.21. For the moderate and severe course, the regressions were as follows: healthcare Ri 2,3 (%) = 0.23 × (Age – 20) + 2.46; industry Ri 2.3(%) = 0.14×(Age – 20) – 1.29. Conclusions: In different age groups, the relative risk of a mild course of COVID-19 in healthcare workers is 1.2–2.1 times higher than in industrial workers while that of a moderate and severe course is already 3 to 9 times higher. The direction of the age-specific COVID-19 risk depends on the disease severity. As for the mild course, a one-year increase in age is associated with a decrease in the disease risk by an average of 0.15 % in healthcare workers and 0.24 % in industrial workers. As for the moderate and severe courses, a one-year increase in age is associated with an increase in the COVID-19 risk by 0.23 % and 0.14 % in healthcare and industrial workers, respectively.