Coronavirus infection COVID-19 in children: a literature review

Introduction. In late 2019, a new subtype of coronavirus named severe acute respiratory syndrome-related coronavirus 2 (SARSCoV-2) rapidly spread around the world, causing a global pandemic. Initially, the proportion of confirmed cases among children was relatively small, and it was believed that children were rarely infected. Subsequent observations have shown that in children and adolescents, the infection is either asymptomatic or accompanied by minimal clinical symptoms, and therefore the true incidence is underestimated due to the low level of testing.

Aim. To summarize and systematize the results of studies on the prevalence, diagnosis, clinical picture, vaccination and treatment of children with a new coronavirus infection COVID-19.

Materials and methods. PubMed searched articles published up to January 15, 2022 using combinations of the following words: COVID-19, SARS-CoV-2, children, pediatrics, adolescents, infants, and school. We read the abstracts of 101 articles and selected 78 articles based on their relevance to the topics discussed. We also analyzed 3 articles on vaccination of children. A total of 89 articles were included in the review.

Results. The SARSCoV-2 positivity rate throughout the peak of the pandemic in children was low compared to adults, including those who had an acute respiratory infection. Children are not only less likely to become infected with the virus, but they also carry the infection more easily than adults. The mortality rate in children with COVID-19 was < 0.5%. In most children, infection is either asymptomatic or accompanied by an erased clinical picture. Vaccination of children and adolescents is recommended mainly to achieve herd immunity in all age groups. However, there are no convincing data on the duration of the immune response, the level of the required protective antibody titer, as well as on the long-term side effects of vaccination due to the insufficient follow-up period and the uncertainty of the immune response criteria.

Conclusion. As information is accumulated on the viral load of children and adolescents, their role in the transmission of the virus, diagnostic approaches in this age group are optimized. The effectiveness of the treatment was tested on patients admitted to the hospital, and recommendations for treatment were developed. Currently, global research efforts are focused on the protection of especially vulnerable children, the prospects for total childhood vaccination, its effectiveness and safety. 

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