Isolation of azole-resistant Aspergillus fumigatus from the environment in the south-eastern USA

Abstract

These findings suggest the development of resistance to azole antifungals in A. fumigatus may be present where agricultural azoles are used in the USA.

Detection of TR 34 /L98H CYP51A Mutation through Passive Surveillance for Azole-Resistant Aspergillus fumigatus in the United States from 2015 to 2017

“…As a result, resistant isolates likely persist alongside wild-type isolates in the environment (the frequency with which this happens in the United States is unknown). We recently identified azole-resistant A. fumigatus containing the TR 34 mutation in an experimental peanut field in Georgia that had been treated with azole fungicides (18). In the present study, Georgia contributed more clinical isolates to our survey than any other state, but we did not observe the TR 34 mutation from any of these isolates.…”

“…DNA sequence analysis of the CYP51A gene was performed for any isolate with elevated MICs confirmed via broth microdilution, as previously described (18). Sequencing revealed that 14 of 20 isolates contained an amino acid substitution in Cyp51A (Table 1).…”

Evidence for the agricultural origin of antimicrobial resistance in a fungal pathogen of humans

“…The samples were processed as described previously by Snelder et al 9 and Hurst et al 16 with some modifications. Briefly, 2 g of soil was suspended in 15 ml of sterile 0.1 M sodium pyrophosphate.…”

“…In the Unites States (U.S.), azole-resistant A. fumigatus strains with TR 34 /L98H and TR 46 /Y121F/T289A alleles have been recently reported in patients 14,15 . Additionally, azole-resistant A. fumigatus isolates with TR 34 /L98H alleles were detected in a peanut field in Georgia 16 . Otherwise, very little information about the frequency of azole-resistant A. fumigatus in agricultural settings in the U.S. is available.…”

Efficacy of metabolites of a Streptomyces strain (AS1) to control growth and mycotoxin production by Penicillium verrucosum, Fusarium verticillioides and Aspergillus fumigatus in culture

“…A. fumigatus also produces the mycotoxin gliotoxin (GLI) (Kupfahl et al 2008). Indeed, in Manchester, UK, azole-resistant strains were first detected in 1999 (Howard et al 2009) and are now commonly found in Switzerland, USA, India and China (Hurst et al 2017;Lockhart et al 2011;Riat et al 2018). However, at the present time, no regulations exist with regard to GLI exposure.…”