Culturable mycobiota of drinking water in Göteborg (Sweden) in comparison to Ljubljana (Slovenia) with implications on human health.

The European Union currently has no specific regulations on fungi in water. The only country where fungi are listed as the parameter is Sweden, with the maximal number of 100 CFU per 100 mL. The present study thus compared culturable mycobiota from Swedish drinking water with Slovenian, which has no specific requirements for fungi. Fungi were isolated with up to 38 CFU/L from 75% of Swedish samples. The most common were the genera Varicosporellopsis (27.3%), Paracremonium (14.5%), and black yeasts Cadophora, Cyphellophora, and Exophiala (18.2%). Using the same sampling and isolation methods, 90% of tap water samples in Slovenia were positive for fungi, with Aspergillus spp. (46%), Aureobasidium melanogenum (36%), and Exophiala spp. (24%) being the most common. The observed differences between countries are likely the consequence of geographical location, the use of different raw water sources, and water treatment methods. However, the core species and emerging fungi Aspergillus fumigatus, Candida parapsilosis sensu stricto, Exophiala phaeomuriformis, Bisifusarium dimerum, and Rhodotorula mucilaginosa were isolated in both studies. These findings point out the relevance of tracking the presence of emerging fungi with known effects on health in drinking water and encourage further studies on their transmission from raw water sources to the end-users.

Low in vitro activity of sertaconazole against clinical isolates of dermatophyte.

BACKGROUND AND PURPOSE: Dermatophytes are a group of fungi specialized in invading humans and other vertebrate keratinized tissues. These fungi cause a variety of skin, nail, and hair disorders, called dermatophytosis (tinea). In some cases, drug resistance to antifungals necessitates special treatment. Among the antifungal agents, sertaconazole (i.e., a third-generation imidazole) has a broad-spectrum against dermatophyte species. Regarding this, the present study was conducted to investigate the antifungal susceptibility of dermatophytes obtained from patients with dermatophytosis in Mashhad located in northeastern Iran. MATERIALS AND METHODS: A total of 75 clinical dermatophyte isolates, including Trichophyton mentagrophytes (n=21), T. interdigital (n=18), T. tonsurans (n=16), Epidermophyton floccosum (n=11), Microsporum canis (n=5), Nannizzia fulvum (n=2), T. benhamiae (n=1), and T. verrucosum (n=1), were evaluated against five antifungal agents of sertaconazole, itraconazole, clotrimazole, terbinafine, and griseofulvin based on the CLSI M38-A2 guideline. RESULTS: According to the results, the minimum inhibitory concentration (MIC) ranges of sertaconazole, terbinafine, griseofulvin, itraconazole, and clotrimazole were estimated at 0.125-16, 0.002-1, 0.5-4, 0.031-4, and 0.016-4 µg/ml, respectively, for dermatophyte species. In addition, the geometric mean (GM) values of the MIC of sertaconazole, terbinafine, griseofulvin, itraconazole, and clotrimazole were obtained as 3.39, 1, 1.44, 1.52, and 1.93, respectively. CONCLUSION: Among the tested antifungals, terbinafine and griseofulvin were the most effective agents against dermatophyte isolates. However, sertaconazole, a third-generation imidazole, did not show any significant effect. Furthermore, M. canis and E. floccosum showed the best response to the antifungal agents.

Ecology of the Human Opportunistic Black Yeast Exophiala dermatitidis Indicates Preference for Human-Made Habitats.

Exophiala dermatitidis is an ascomycetous black yeast from the order Chaetothyriales. Its growth characteristics include the polymorphic life cycle, ability to grow at high and low temperatures, at a wide pH range, survival at high concentrations of NaCl, and survival at high UV and radioactive radiation. Exophiala dermatitidis causes deep or localized phaeohyphomycosis in immuno-compromised people worldwide and is regularly encountered in the lungs of cystic fibrosis patients. Regardless of numerous ecological studies worldwide, little is known about its natural habitat or the possible infection routes. The present review summarizes the published data on its frequency of occurrence in nature and in man-made habitats. We additionally confirmed its presence with culture-depending methods from a variety of habitats, such as glacial meltwater, mineral water, mineral-rich salt-pan mud, dishwashers, kitchens and different environments polluted with aromatic hydrocarbons. In conclusion, the frequency of its recovery was the highest in man-made indoor habitats, connected to water sources, and exposed to occasional high temperatures and oxidative stress.

Candida and Fusarium species known as opportunistic human pathogens from customer-accessible parts of residential washing machines.

Energy constraints have altered consumer practice regarding the use of household washing machines. Washing machines were developed that use lower washing temperatures, smaller amounts of water and biodegradable detergents. These conditions may favour the enrichment of opportunistic human pathogenic fungi. We focused on the isolation of fungi from two user-accessible parts of washing machines that often contain microbial biofilms: drawers for detergents and rubber door seals. Out of 70 residential washing machines sampled in Slovenia, 79% were positive for fungi. In total, 72 strains belonging to 12 genera and 26 species were isolated. Among these, members of the Fusarium oxysporum and Fusarium solani species complexes, Candida parapsilosis and Exophiala phaeomuriformis represented 44% of fungi detected. These species are known as opportunistic human pathogens and can cause skin, nail or eye infections also in healthy humans. A machine learning analysis revealed that presence of detergents and softeners followed by washing temperature, represent most critical factors for fungal colonization. Three washing machines with persisting malodour that resulted in bad smelling laundry were analysed for the presence of fungi and bacteria. In these cases, fungi were isolated in low numbers (7.5 %), while bacteria Micrococcus luteus, Pseudomonas aeruginosa, and Sphingomonas species prevailed.