The Environmental Spread of <i>Aspergillus Terreus</i> in Tyrol, Austria

• Main Authors: Anna-Maria Dietl, Roya Vahedi-Shahandashti, Carmen Kandelbauer, Bart Kraak, Michaela Lackner, Jos Houbraken, Cornelia Lass-Flörl
• Format: Article
• Language: English
• Published: MDPI AG 2021-03-01
• Series: Microorganisms
• Subjects: <i>Aspergillus terreus</i>; environmental distribution; epidemiology; antifungal susceptibility testing; environmental exposure; airborne pathogen
• Online Access: https://www.mdpi.com/2076-2607/9/3/539

Fungal infections due to <i>Aspergillus</i> species have become a major cause of morbidity and mortality among immunocompromised patients. At the Medical University of Innsbruck, <i>A. terreus</i> and related species are the second most common causative agents of aspergillosis. In this one-year study we collected environmental samples to investigate (i) the environmental distribution, (ii) the ecological niche of <i>A. terreus</i> in Tyrol, (iii) the genetic relatedness of environmental and clinical isolates and the correlation between those two groups of isolates, and (iv) the antifungal susceptibility patterns. <i>A. terreus</i> was present in 5.4% of 3845 environmental samples, with a significantly higher frequency during winter (6.8%) than summer (3.9%). An increased <i>A. terreus</i> abundance in Tyrol’s Eastern part was detected which is in agreement with the proof of clinical cases. In total, 92% of environmental and 98% of clinical <i>A. terreus</i> isolates were amphotericin B resistant; 22.6% and 9.8% were resistant against posaconazole. Overall, 3.9% of clinical isolates were resistant against voriconazole. Short tandem repeat analysis identified three major genotypes persisting in Tyrol. Soil from agricultural cornfields seems to be an important source; the environmental frequency of <i>A. terreus</i> correlates with the high incidence of <i>A. terreus </i>infections in certain geographical areas.