Epidemiology and Prevalence of Azole-Resistant Aspergillus fumigatus: What Is Our Understanding of the Situation?

Purpose of the Review: Azole-resistant Aspergillus fumigatus is an emerging clinical problem. Resistance can develop both with clinical exposure and with environmental exposure to azole and azole-like fungicides used against phytopathogens. Here, our current understanding of the epidemiology and prevalence of this emerging problem is reviewed. Recent Findings: Azole-resistant A. fumigatus is now a worldwide problem, as it has been documented in clinical and environmental samples on all but one continent. Although Europe has been the center of this issue, hotspots are now emerging in Asia. However, there are several limitations to our current understanding of the extent of this problem, including issues with surveillance strategies and our reliance on phenotypic methods for detecting resistance. Summary: Azole-resistant A. fumigatus is an emerging issue both clinically and in the environment that requires greater attention in order to preserve this very useful class of antifungal agents for the treatment of aspergillosis.