Azole Resistance of Environmental and Clinical Aspergillus fumigatus Isolates from Switzerland.

is a ubiquitous opportunistic pathogen. This fungus can acquire resistance to azole antifungals due to mutations in the azole target (). Recently, mutations typical for environmental azole resistance acquisition (for example, TR/L98H) have been reported. These mutations can also be found in isolates recovered from patients. Environmental azole resistance acquisition has been reported on several continents. Here we describe, for the first time, the occurrence of azole-resistant isolates of environmental origin in Switzerland with mutations, and we show that these isolates can also be recovered from a few patients. While the TR/L98H mutation was dominant, a single azole-resistant isolate exhibited a mutation (G54R) that was reported only for clinical isolates. In conclusion, our study demonstrates that azole resistance with an environmental signature is present in environments and patients of Swiss origin and that mutations believed to be unique to clinical settings are now also observed in the environment.