Diversidade de espécies fúngicas na água de rede pública de São José do Rio Preto

Abstract

The survival capacity of fungi in the water is high and their transmission through drinking water changes the drinking standard and causes damage to public health when ingested or in contact with the skin and mucous, especially in hospitals. In the presence of Aspergillus spp., Fusarium spp., Penicillium spp., Rhodotorula spp. and other fungi less frequent in the water distribution systems together with the Physical-chemical conditions present, biofilm formation may occur causing phenotypic changes in virulence and antimicrobial resistance, as well as the liberation of metabolism products that in contact with humans and animals, become potential risks for allergic processes and intoxication. Brazilian and international guidelines establish standards water quality control, streghtening physical-chemical and microbiological standards, for with no fungi’s inclusion. Objectives: The objectives of this study were to investigate the occurrence and distribution of species of filamentous fungi and yeast in the water supply network; to correlate the occurrence of fungi in water with seasonality and to analyze the phenotypic profile of antimicrobial susceptibility of yeast. Material and Methods: Water samples from 245 different points of the water supply network of a municipality in the interior of the State of São Paulo - Brazil - were collected after 15 days of the beginning of each season, 100 ml of water were collected and sent to the Laboratory of Microbiology of Medical School of São José do Rio Preto - FAMERP for analysis. Morphological, physiological and biochemical characteristics were used for the definition of fungal species and analysis of antimicrobial susceptibility. Statistical analysis used the Z test to compare proportions and the Chi-Square test to evaluate dependency or associability. Results: A total of 26.3% of the samples was positive for filamentous fungi with the Fusarium spp. prevalent in spring, summer, winter and Penicillium spp. in the fall. For yeasts, 11.4% of the samples were positive, with the species Rhodotorula minuta prevalent in spring, fall, summer and the complex Candida parapsilosis in the winter. The resistance phenotype appeared in 66.5% of isolated yeast, being Rhodotorula minuta the prevalent resistant species found in the present study. Conclusions: The presence filamentous fungi and yeasts in the water, especially Fusarium spp. and Rhodotorula spp. is a public health concern because they are common opportunistic pathogens in human and animal infections. Therefore, frequent monitoring of these microorganisms in the standard protocols of water supply network for analyses of quality control important.