Determination of anti-pertussis antibodies in schoolchildren with long-term cough

Abstract

Objective: to assess anti-pertussis immunity in schoolchildren aged 7–17 who complained of a prolonged cough during the 11-year follow-up period. Materials and methods. The study included 1046 patients aged 7 to 17 years who applied to the Consultative and Diagnostic Center of the G.N. Gabrichevsky Research Institute of Epidemiology and Microbiology with complaints of prolonged cough in the period from 2010 to 2020. Blood serums were examined in ELISA with the determination of IgM, IgG, IgA antibodies using RIDASCREEN test system (Germany). Results. An active infection with the detection of IgM and/ or IgA, IgG antibodies above threshold levels was detected in 51,3% of children with prolonged cough, while annually in a fairly high percentage throughout the follow-up period. Active pertussis infection, established based on the detection of IgM, IgG, IgA antibodies above thresholds in blood serum samples, prevailed in children 12–15 years old, accounting for more than 60% in children with prolonged cough. Antipertussis immunity as a result of childhood vaccination or previous disease was detected in 16.1-20.2% of people in the period 2010–2014 and in 12,8-20,9% in 2015–2020. Conclusion. The results obtained by us on the study of anti-pertussis immunity in schoolchildren confirm the presence of active latent circulation of the pathogen whooping cough among children of this age cohort and, therefore, the presence of unaccounted for cases of the disease. This confirms the importance of timely diagnosis of pertussis, isolation of children for the period of active infection and justifies the need for the widespread introduction of a second revaccination against pertussis.