COVID-19 Seroprevalence in Children during Pandemic Waves in Sarajevo, a Single Center Experience.

Objective. The aim of this study was to present data on the prevalence of seropositive children tested in the laboratory of the Eurofarm polyclinic in Sarajevo, from September 2020 to May 2021. Material and Methods. Peripheral blood samples were collected and anti-SARS-CoV-2 antibodies were detected using an electrochemiluminescence immunoassay. Results. In the total of 762 tested children, 187 were positive (24.5%), based on cut-off value. Of all the positive cases 42.8% were female while 57.2% were male. There were 10.1% of positive children in the first age group (0-5 years), 44.4% in the second group (6-13 years), and 45.5% in the third group (14-18 years). There was no statistically significant difference in seroprevalence between age groups and gender. The lowest seroprevalence (3.6%) was observed in October 2020 after the first pandemic wave, and the highest seroprevalence (60.3%) was observed in April 2021, corresponding to the third pandemic wave. Conclusion. The results of our study showed that the seroprevalence in children was low, especially during the first year of the pandemic. In the second year of the pandemic, there was an evident statistically significant increase in the number of seropositive children. Similar data have been shown in studies for adults. [ABSTRACT FROM AUTHOR]