Modern Pediatrics. Ukraine. (2023). 4(132): 62-66. doi 10.15574/SP.2023.132.62
Shlyakhova N. V.², Rak L. I.¹, Shevchenko N. S.^1,3, Holovko T. O.^1,3
1SІ «Institute for Children and Adolescents Health Care of the NAMS of Ukraine», Kharkiv
²Kharkiv State Academy of Physical Culture, Ukraine
³V.N. Karazin Kharkiv National University, Ukraine

For citation: Shlyakhova NV, Rak LI, Shevchenko NS, Holovko TO. (2023). Prevalence of antibodies to SARS-COV-2 in children and adolescents: a single-center study. Modern Pediatrics. Ukraine. 4(132): 62-66. doi 10.15574/SP.2023.132.62.
Article received: Feb 21, 2023. Accepted for publication: May 16, 2023.

Despite the fact that children with COVID-19 are usually asymptomatic or mild, infection with SARS-CoV-2 is more likely to lead to the development of an antibody response. Understanding humoral immunity to SARS-CoV-2, including in children, is critical for future public health and vaccination strategies. Children with chronic diseases deserve special attention.
Purpose – to study the prevalence of positive antibodies to SARS-CoV-2 in children and adolescents who were in paediatric hospital without signs of viral disease to develop future healthcare strategies.
Materials and methods. In 32 children aged 6-17 years (14 (43.8%) boys and 16 (56.2%) girls) quantitative determination of IgG antibodies to SARS-CoV-2 in blood serum was carried out by enzyme immunoassay using commercial SARS-CoV-2 S1\RBD IgG Ab ELISA (TECAN, IBL International GmbH, Germany).
Results. The majority (n=27, 84.4%) of children had a positive level of class G antibodies to SARS-CoV-2. 7 (25.9%) children had a positive PCR test in their anamnesis, 6 (18.8%) persons provided information about the infection transmitted by family members. Clinical manifestations characteristic of SARS-CoV-19 were present in 2 (7.4%) children. Parents of 18 (66.7%) children claimed that their children had no symptoms of COVID-19, while family members of 6 (33.3%) children had cases of the disease. All children (n=6, 18.8%) who were vaccinated with two doses of Comirnaty® vaccine had positive IgG antibodies to SARS-CoV-2. Antibodies to SARS-CoV-2 were absent in 5 (15.4%) people, all of them were patients with type 1 diabetes.
Conclusions. The study of the prevalence of antibodies to SARS-CoV-2 provides important information about circulating antibodies against SARS-CoV-2 in children and adolescents, in particular those with chronic diseases. The obtained results showed the predominant seropositivity of children, which is formed regardless of the clinical manifestations of the disease. A high level of antibodies under the conditions of revaccination confirms the benefit of revaccination of children to strengthen memory formation.
The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of the participating institution. The informed consent of the patient was obtained for conducting the studies.
No conflict of interests was declared by the authors.
Keywords: children, SARS-CoV-2, antibodies, prevalence, humoral immunity.

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