TB transmission among children

Background: Tuberculosis (TB) remains a global health concern, with rising pediatric and adolescent cases. The advancement of diagnostic strategies is essential for effective control, with whole genome sequencing (WGS) emerging as a promising tool. This study explores using WGS in pediatric TB cases to characterize transmission. Methods: Mycobacterium tuberculosis isolates from pediatric patients, and their contacts were collected between January 2023 and June 2024 in Slovakia and the Czech Republic. The isolates were subjected to WGS to characterise the resistance patterns and transmission. Results: A total of 37 patients were followed in this study, comprising 30 patients and 7 adults as contacts. The phylogenetic analysis results revealed that 32 out of 37 (86.5%) isolates belonged to the Euro-American lineage. In 5 isolates (13,5%), the East-Asian lineage dominated. Genotypic resistance to at least one drug was confirmed in 6 patients (16%). 24 patients were divided into 9 clusters (65%), leaving 13 unclustered (35%). Moreover, the concordance between the identification of source case by WGS and epidemiological anamnesis was confirmed in 60% of patients. Conclusion: Epidemiological data may not always provide accurate insights of TB transmission. Consequently, integrating molecular methods, such as WGS, is essential to enhance the reliability and precision of epidemiological analyses.