Microbiological monitoring of coagulase-negative Staphylococcus in public drinking water fountains: Pathogenicity factors, antimicrobial resistance and potential health risks.

The presence of opportunistic bacteria such as coagulase-negative Staphylococcus (CoNS) in drinking water poses public health concerns because of its potential to cause human infection and due to its antimicrobial resistance (AMR) diversity. This study evaluated the occurrence, virulence markers and AMR of CoNS in 468 drinking water samples from 15 public fountains located in four urban parks of São Paulo city (Brazil). Out of 104 samples positive for the presence of Staphylococcus genus, we detected CoNS in 75 of them (16%), which did not meet the Brazilian sanitary standards for residual chlorine. All isolates were of concern to public health for being responsible for infection in humans from low to high severity, nine of them are considered the most of concern due to 63.6% being multiresistant to antimicrobials. The results demonstrated that CoNS in drinking water must not be neglected. It is concluded that the presence of resistant staphylococci in drinking water is a potential health risk, which urges feasible and quick control measures to protect human health, especially in crowded public places.

Sanitation assessment of wastewater treated by stabilization ponds for potential reuse in agricultural irrigation sanitation assessment.

Wastewater reuse has become an important alternative to agricultural irrigation; on the other hand, it poses concern with regard to public health. Total coliform and Escherichia coli concentration, presence of helminth eggs and Salmonella, and physical-chemical parameters were evaluated in raw and treated wastewater. Chemical and biochemical oxygen demand removal efficiency was 74.6 and 77.9%, respectively. As for organic nitrogen, total phosphorus, and total suspended solids, total efficiency removal was 17.4, 12.5, and 32.9%, respectively. The average density of total coliforms and E. coli was 3.5 x 10(9) and 1.8 x 10(8) MPN/100 mL and 1.1 x 10(7) MPN/100 mL and 3.9 x 10(5) MPN/100 mL for raw and treated wastewater, respectively. Ascaris eggs were observed in 80.8% of the samples collected, and viable eggs in 42.3% of the samples. Salmonella was detected in 36.4% of the samples. The values observed in treated wastewater did not show the adequate bacteriological quality, as recommended by World Health Organization (Geneva, Switzerland). Therefore, additional measures should be taken to achieve an improved microbiological and parasitological quality.