Pan-azole resistance in clinical Aspergillus fumigatus isolates carrying TR34/L98H from birds and mammals in Belgium

Aspergillosis causes significant health risks to both birds and mammals. The outcome of these infections is often poor due to delayed diagnosis and treatment failure. We investigated 152 cases of aspergillosis from birds and mammals in Belgium. Most samples originated from the taxonomic orders Artiodactyla (40.1 %) and Columbiformes (19.7 %). Five isolates (3.3 %) showed phenotypical resistance against at least one medical azole. Three of these isolates were pan-azole resistant bearing the TR34/L98H mutation. The predominance of this resistance mutation supports an environmental route for exposure and resistance selection, highlighting the importance of the One Health concept.