Changes in the epidemiological situation of multidrug-resistant tuberculosis in Poland in the years 2018-2022.

Introduction: The presented analysis was conducted against the backdrop of the global pandemic and the Russian-Ukrainian war. The conflict on Poland's eastern border raised concerns about potential deterioration of the epidemiological situation in Poland due to the influx of immigrants from countries with a high incidence of multidrug‑resistant (MDR) tuberculosis (TB) and the Beijing genotype.

Objectives: We aimed to assess the epidemiological situation of MDR‑TB in Poland from 2018 to 2022 and to analyze the prevalence of the Beijing genotype in both the Polish and immigrant populations.

Patients and methods: The study group comprised 250 patients with bacteriologically confirmed MDR‑TB, diagnosed between 2018 and 2022. Microbiological, phenotypic, and molecular analyses were performed.

Results: Significant changes were observed in the number of MDR‑TB cases, with a notable increase in registered cases after the outbreak of the war. One in 3 patients was infected with pre‑XDR strains, and 1 in 4 with XDR strains. A total of 40% of cases were resistant to fluoroquinolones, with higher resistance rates observed among Polish patients than the immigrants. MDR as well as MDR with resistance to second‑line injectable drugs were identified more often among the immigrants than the Polish population. The Beijing genotype dominated with 179 isolates (71.6%), identified with a similarly high frequency in both the immigrant and Polish populations.

Conclusions: The war in Ukraine caused a massive influx of immigrants to Poland, many of whom were infected with MDR and Beijing strains of TB. There is a significant risk of an increase in the incidence of MDR‑TB in Poland in the future, as well as a potential for TB transmission between the immigrants and the native population.