The high diversity of Scedosporium and Lomentospora species and their prevalence in human-disturbed areas in Taiwan

Scedosporium and Lomentospora are important opportunistic pathogens causing localized or disseminated infection in humans. Understanding their environmental distribution is critical for public hygiene and clinical management. We carried out the first environmental survey in urbanized and natural regions in Taiwan. Overall, Scedosporium and Lomentospora species were recovered in 130 out of 271 soil samples (47.9%) across Taiwan. We morphologically and molecularly identified five Scedosporium species and one Lomentospora species. All four major clinical relevant species were isolated with high frequency, i.e. S. apiospermum (42.5%), S. boydii (27.5%), L. prolificans (15.0%), and S. aurantiacum (8.8%); two clinically minor species, S. dehoogii (5.6%) and S. haikouense (0.6%), had moderate incidence. These fungal species have high incidence in urban (48%) and hospital (67.4%) soil samples, and have limited distribution in samples from natural regions (5%). Multivariate analysis of the fungal composition revealed strong evidence of the preferential distribution of these fungi in urban and hospital regions compared to natural sites. In addition, strong evidence suggested that the distribution and abundance of these fungal species are highly heterogeneous in the environment; samples in vicinity often yield varied fungal communities. Our results indicated that these fungal species are prevalent in soil in Taiwan and their occurrences are associated with human activities. Hygiene sensitive places such as hospitals should be particularly aware of the high frequency of the clinical relevant species.