Immune response in new coronavirus infection COVID-19 in children and adults

Abstract

Introduction. It is known that COVID-19 occurs more often in adult patients, especially if they have concomitant somatic diseases, children are at less risk of developing it. The aim of this work is to evaluate and compare immune response parameters in new coronavirus infection COVID-19 in children and adults. Materials and methods. The results of the examination of 56 adults 19-55 years old and 57 children 14-18 years old were included in the work. The examination results of COVID-19 patients were compared with similar data in practically healthy individuals of the corresponding age groups. All patients underwent laboratory tests to determine the following parameters: presence of SARS-CoV-2 RNA, general blood test parameters, major lymphocyte subpopulations, level of total immunoglobulins (IgM, IgG, IgA), number of CIC, absorbance and bactericidal activity of leukocytes.Results. The proportion of positive findings for SARS-CoV-2 RNA in different age groups ranged from 13.6% to 25.8%. General and specific patterns of immune response in patients of different age groups were established. Common features were an increase in the number of circulating immune complexes and activated T-lymphocytes. Differences were noted in the level of serum immunoglobulins IgM and IgG, neutrophil uptake activity, the number of monocytes, as well as in the level of different subpopulations of lymphocytes. Discussion. In adults, changes in the adaptive immune response, including the cellular level, are predominantly expressed. In children, there are signs of inefficiency of innate mechanisms of immune responses. Conclusion. The dynamics of the number of examined and positive findings correlate with similar figures in Russia and have a two-wave pattern. Increased number of circulating immune complexes and activated T-lymphocytes is typical for all patients with new coronavirus infection COVID-19 regardless of age, which is a sign of acute infection-inflammatory process development and insufficiently effective elimination of antigen (pathogen).