Molecular genetic structure of Mycobacterium tuberculosis in Krasnoyarsk region

Introduction. Despite the improvement of the general epidemiological situation for tuberculosis (TB) in Krasnoyarsk region, the spread of multiple and pre-extensive drug resistance (MDR and pre-XDR) of the pathogen remains a serious problem that requires a comprehensive analysis of factors, including an assessment of the circulating population of Mycobacterium tuberculosis. Objective. T o assess the molecular genetic structure of M. tuberculosis strains in Krasnoyarsk region. Materials and methods. A total of 400 strains were studied for 2024 using SNPand MIRU-VNTR-24 typing. Results. High levels of MDR (64.5 %), including pre-XDR (45.0 %) and XDR (1.5 %), were detected in the sample of M. tuberculosis strains. The dominance of L2 (Beijing genotype) was found in newly diagnosed cases (72.1 %) and previously treated patients (85.6 %). Non-Beijing strains belonged to the L4 genotypes (LAM, Ural, Haarlem and S). The most common Beijing subtypes were B0/W148 (49.5 %; 198/400) and Central Asian Russian (25.0 %; 99/400), they differed significantly in MDR levels (96.5 % and 36.4 %, respectively, by subtype; p < 0.001). Beijing B0/W148 strains had the highest levels of preXDR (71.7 %) and XDR (3.0 %). MDR among L4 strains (30.1 %) was significantly lower compared to Beijing (76.4 %) (p < 0.001). Strains from HIV-TB patients were more common with an MDR profile (74.4 %) than from patients without HIV infection (60.4 %) (p = 0.008) against the background of a higher presence of Beijing B0/W148 in the HIVTB group (59.8 % versus 45.2 %; p = 0.008). Conclusion. Beijing B0/W148 strains account for about half of the study sample and make a significant contribution to the pre-XDR (78.9 %) and XDR (100 %), which requires further monitoring and enhanced control of treatment effectiveness.