Environmental reservoirs of the drug-resistant pathogenic yeast Candida auris.

Candia auris is an emerging human pathogenic yeast; yet, despite phenotypic attributes and genomic evidence suggesting that it probably emerged from a natural reservoir, we know nothing about the environmental phase of its life cycle and the transmission pathways associated with it. The thermotolerant characteristics of C. auris have been hypothesised to be an environmental adaptation to increasing temperatures due to global warming (which may have facilitated its ability to tolerate the mammalian thermal barrier that is considered a protective strategy for humans against colonisation by environmental fungi with pathogenic potential). Thus, C. auris may be the first human pathogenic fungus to have emerged as a result of climate change. In addition, the release of antifungal chemicals, such as azoles, into the environment (from both pharmaceutical and agricultural sources) is likely to be responsible for the environmental enrichment of resistant strains of C. auris; however, the survival and dissemination of C. auris in the natural environment is poorly understood. In this paper, we critically review the possible pathways through which C. auris can be introduced into the environment and evaluate the environmental characteristics that can influence its persistence and transmission in natural environments. Identifying potential environmental niches and reservoirs of C. auris and understanding its emergence against a backdrop of climate change and environmental pollution will be crucial for the development of effective epidemiological and environmental management responses.

Study of the persistence of selected Gram-negative bacteria pathogens of healthcare-associated infections on hospital fabrics.

BACKGROUND: The ability of healthcare associate infection (HAI) pathogens to persist on fomites is crucial to their transmission within the healthcare setting, this study evaluated the persistence of 3 common HAI pathogens on fabrics materials commonly used in healthcare settings. METHODS: Persistence of bacteria species on fabric was investigate by inoculating standardized inoculum prepared from the clinical isolates of Pseudomonas aeruginosa, Escherichia coli and Acinetobacter baumannii on sterile swatches of 100% cotton, microfiber and polyester. Viable bacteria persisting on the inoculated fabrics were evaluated immediate after inoculation and subsequently at 96-hour interval for 32 days using the drop plate technique. The effect of moisture on the persistence of the studied bacteria isolates was also evaluated. RESULTS: Between 3 and 6 log reduction in the viability of the inoculated bacteria cells were observed after 32 days of inoculation on fabrics. Generally, lower viable cells were recovered from the microfiber fabrics compared to others, while higher viable cells were recovered from wet fabrics compared to the dry fabrics in this study. DISCUSSION AND CONCLUSIONS: This study demonstrated that HAI bacteria pathogens can persist for more than a month on hospital fabrics, and that their persistence can be enhanced by moisture.