Occurrence, antifungal susceptibility, and virulence factors of opportunistic yeasts isolated from Brazilian beaches
Maciel, N.O.P.; Johann, S.; Brandão, L.R.; Kucharikova, S.; Morais, C.G.; Oliveira, A.P.; Freitas, G.J.C.; Borelli, B.M.; Pellizzari, F.M.; Santos, D.A.; Van Dijck, P.; Rosa, A. (2019). Occurrence, antifungal susceptibility, and virulence factors of opportunistic yeasts isolated from Brazilian beaches. Mem. Inst. Oswaldo Cruz, Rio de Janeiro 114: 15. https://dx.doi.org/10.1590/0074-02760180566 In: Memórias do Instituto Oswaldo Cruz. Instituto Oswaldo Cruz: Rio de Janeiro. ISSN 0074-0276; e-ISSN 1678-8060, more |   |
| Keywords | Candida albicans
Marine/Coastal | | Author keywords | opportunistic pathogenic yeasts; beaches; Escherichia coli; Candidaalbicans; yeast adhesion; disseminated infection tests |
| Authors | | Top | - Maciel, N.O.P.
- Johann, S.
- Brandão, L.R.
- Kucharikova, S., more
| - Morais, C.G.
- Oliveira, A.P.
- Freitas, G.J.C.
- Borelli, B.M.
| - Pellizzari, F.M.
- Santos, D.A.
- Van Dijck, P., more
- Rosa, A.
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| Abstract | BACKGROUNDOpportunistic pathogenic yeast species are frequently associated with water habitats that have pollution sources of human or animal origin. Candida albicans has already been suggested as a faecal indicator microorganism for aquatic environments.OBJECTIVESThe goal of this study was to investigate the occurrence of C. albicans and other opportunistic yeasts in sand and seawater samples from beaches in Brazil to assess their correlation with Escherichia coli, and to characterise the pathogenic potential of the yeast isolates.METHODSOpportunistic species (yeasts that grow at 37ºC) were isolated from sand and seawater samples from eight beaches in Brazil during the summer and the winter. Opportunistic yeast species were evaluated for their susceptibility to antifungal drugs, virulence factors, and the in vitro and in vivo biofilm formation. Strains were selected to carry out virulence tests using BALB/c mice.FINDINGSSeveral water samples could be classified as inappropriate for primary contact recreation in relation to E. coli densities. C. albicans was isolated in low densities. Of the 144 opportunistic yeasts evaluated, 61% displayed resistance or dose-dependent sensitivity to at least one tested drug, and 40% produced proteinase. Strains of C. albicans and Kodamaea ohmeri exhibited the highest rates of adhesion to buccal epithelial cells. All the C. albicans strains that were tested were able to undergo morphogenesis and form a biofilm on catheter fragments in both in vitro and in vivo experiments. It was possible to confirm the pathogenic potential of three of these strains during the disseminated infection test.MAIN CONCLUSIONSThe identification of opportunistic yeast species in seawater and sand samples from Brazilian beaches suggest a potential risk to the health of people who use these environments for recreational purposes. |
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