Characteristics of Spirography Indicators in Unvaccinated Schoolchildren with Specific Immunity to SARS-CoV-2

Introduction: The impact of the novel coronavirus disease on human health and its long-term outcomes, including that in the child population, remains a pressing issue. The course of the disease in children is milder than in adults, but the incidence rate has not shown a downward trend since 2020. Respiratory symptoms such as cough and shortness of breath persist in children for a long time, regardless of the disease severity.

Objective: Тo establish characteristics of spirography indicators in unvaccinated schoolchildren with specific immunity to SARS-CoV-2.

Materials and methods: The present study included 169 schoolchildren aged 7–14 years. The observation group consisted of 90 children with specific Class G immunoglobulins to SARS-CoV-2 in their blood serum and the reference group consisted of 79 children matched by age having no IgG antibodies to the virus. All subjects underwent a pulmonary function test and the spirography results were then compared using classical methods of descriptive statistics.

Results: The median indicators of forced vital capacity and forced expiratory volume in the first second measured by spirometry were within the normal range in both groups. In the observation group, statistically lower values of the median of the modified Tiffeneau-Pinelli index (%) and that of the peak expiratory flow rate (%) (p = 0.001) were established, with the latter being 2.8 times more frequent (p = 0.021).

Conclusion: The revealed changes in spirography parameters in the schoolchildren who were not vaccinated against COVID-19 but had IgG antibodies to SARS-CoV-2 may indicate mild post-COVID obstructive respiratory dysfunction.

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