An Integrated Analysis Approach to Unravel the Aspergillus Community in the Hospital Environment

Area of Science:

• Environmental microbiology
• Hospital epidemiology
• Medical mycology

Background:

• The genus Aspergillus is ubiquitous and can cause serious infections, particularly in immunocompromised individuals.
• Rising azole resistance in Aspergillus necessitates better control strategies in healthcare settings.
• Hospital environments require thorough assessment for fungal contamination to mitigate infection risks.

Purpose of the Study:

• To assess the prevalence and diversity of Aspergillus species in Spanish hospital environments.
• To compare the effectiveness of culture-based and environmental DNA (eDNA)-based methods for Aspergillus detection.
• To identify high-risk areas within hospitals for Aspergillus contamination.

Main Methods:

• Conducted a large-scale environmental survey of air and surface samples from three Spanish hospitals.
• Employed integrated approaches including general and selective cultivation at different temperatures (28°C and 37°C).
• Utilized environmental DNA (eDNA)-based analyses for molecular identification of Aspergillus species.

Main Results:

• Aspergillus was detected in nearly all indoor hospital zones, predominantly in air samples.
• The relative abundance of Aspergillus varied significantly by method, ranging from 1.4% (eDNA) to 28.3% (cultivation at 37°C).
• Intensive care units showed the highest proportion of Aspergillus eDNA, and 32 species across 10 sections were identified, including key pathogens like A. fumigatus.

Conclusions:

• Aspergillus species are widespread in hospital environments, with higher detection rates in critical areas like ICUs.
• Environmental monitoring using both cultivation and eDNA techniques is essential for effective fungal burden control.
• Identifying specific Aspergillus species and their distribution aids in developing targeted infection control strategies in hospitals.