Geographically structured genotypes and resistance clustering in Aspergillus fumigatus

We analysed 498 global Aspergillus fumigatus isolates using multilocus variable-number tandem-repeat (MLVA) typing to investigate regional clustering, environmental–clinical overlap, and azole resistance patterns. The dataset, which included 155 newly genotyped Korean strains, revealed extensive genotypic diversity and four distinct phylogeographic clusters. Resistance-associated mutations (TR34/TR46) appeared concentrated within certain clusters that largely comprised isolates from Germany, South Korea, and China, suggesting country-level enrichment rather than broader continental trends. These findings support the presence of geographically structured populations and localised emergence of resistance and demonstrate the utility of MLVA for molecular surveillance, particularly in settings where whole-genome sequencing is limited.