High Azole Resistance in Aspergillus fumigatus Isolates from Strawberry Fields, China, 2018.


Chen Y, Dong F, Zhao J, Fan H, Qin C, Li R, Verweij PE, Zheng Y, Han L.
Emerg Infect Dis. 2020 Jan;26(1):81-89.


In 2018, we conducted a cross-sectional study to investigate azole resistance in environmental Aspergillus fumigatus isolates obtained from different agricultural fields in China. Using 63 soil cores, we cultured for azole-resistant A. fumigatus and characterized isolates by their cyp51A gene type, short tandem repeat genotype, and mating type. Of 206 A. fumigatus isolates, 21 (10.2%) were azole resistant. Nineteen of 21 had mutations in their cyp51A gene (5 TR34/L98H, 8 TR34/L98H/S297T/F495I, 6 TR46/Y121F/T289A). Eighteen were cultured from soil samples acquired from strawberry fields, suggesting this soil type is a potential hotspot for azole resistance selection. Twenty resistant isolates were mating type MAT1-1, suggesting asexual sporulation contributed to their evolution. Prochloraz, difenoconazole, and tebuconazole were the most frequently detected fungicides in soil samples with azole-resistant fungus. Our study results suggest that managing the fungicides used in agriculture will help contain the problem of antifungal drug resistance in clinics.