Healthcare-Associated Invasive Mould Diseases: From Rapid Diagnostics to Safe and Effective Management

Invasive mould diseases (IMDs) are an important component of healthcare-associated infections (HAIs). However, they can be difficult to identify, as the standard definition of HAIs do not always apply and usually have a longer and more variable onset after exposure. Identifying the source of infection is also challenging, as moulds can colonise a wide range of indoor healthcare environments, and multiple sources of exposure are possible. Thus, healthcare-associated IMDs may reflect a broader failure of infection control measures rather than a single isolated event. In addition, IMDs may evolve into outbreaks that are hard to detect and investigate, as they can develop over extended periods before raising concern. Here, we review mould ecology in healthcare settings and describe the patient groups at risk for healthcare-associated IMDs. We also overview the investigative approaches used to identify case clusters—including case finding, environmental sampling and isolate genotyping—summarise major IMD outbreaks and highlight best management practices. Taken together, this knowledge will help identify high-risk situations and guide the implementation of targeted preventive measures and diagnostic strategies that enable the timely diagnosis and effective management of healthcare-associated IMDs.