Aeromonas spp. and microbial indicators in raw drinking water source

Abstract

Aeromonas species are autochtonous in the aquatic environment and some of them have been associated with health effects like wound infections, septicemia and diarrhoeal illness. In this study, the occurrence of Aeromonas spp. and microbial indicators in raw drinking water from wells, springs, fountains and mineral waters was evaluated. A total of 126 water samples was analyzed for Aeromonas spp. by the membrane filtration technique using ADA media and by P/A test. Typical colonies of Aeromonas spp. were submitted to biochemical tests for species differentiation. Toxin production was tested using Y-1 mouse adrenal cells. Coliforms and heterotrophic bacteria were enumerated by membrane filtration and pour plate techniques, respectively. P. aeruginosa, C. perfringens and fecal streptococci were determined by P/A method. Aeromonas spp. were isolated in 36.5% of the samples, whereas total and thermotolerant coliforms were detected in 51.2% and in 23.8% of the samples, respectively. C. perfringens, fecal streptococci and P. aeruginosa were present in 16.5%, 20.4% and 3.8% of the samples, respectively. The concentrations of heterotrophic bacteria were higher than 1,0x10 3 CFU/mL in 52.5% of the samples. A. hydrophila was the most frequent species, followed by A. allosaccharophila, A. jandaei, A.sobria and HG2. A heat label toxin was detected in 13 from the 58 strains tested. These data show that the drinking water sources analyzed can represent a risk for human health. It is important to consider that wells and springs are used as drinking water supply in poor areas and rural regions, where undernourished people more susceptible to infections by these microorganisms predominate.

An Approach Using Non‐Conventional Indicators for Detecting Microbial Water Pollution

“…In this respect, a study was conducted on Mfoundi River watershed at Yaounde in Cameroon, in which the recorded values of Aeromonas were about twofold higher than fecal coliforms . Our results were also in harmony with those previously reported by Kivanc et al Dumonter et al , and Di Bari et al .…”

Incidence and antimicrobial resistance of enteropathogens isolated from an integrated aquaculture system

“…2007). Exposure to water contaminated with Aeromonas spp., through ingestion or contact, has been associated with human infections, which are particularly hazardous in immune‐compromised patients (Bari et al. 2007).…”

“…There are data that illustrate the spread of autochthonous micro‐organisms in an aquatic environment, with a high prevalence of some species of Aeromonas and Vibrio , occurring mainly in fresh water fish (Hirsch et al. 2006; Bari et al. 2007).…”

Evaluation of the Microbiological Quality of Drinking Water in the District of Bragança (Northwest Portugal) throughout a Ten‐Year Period (1996–2005), during the Implementation of the 1998/83 EC Directive

“…A regular incidence of C. perfringens spores in groundwater samples from public springs used for direct human consumption was detected in Spain (Araujo et al, 2004) where 40 of 51 groundwater samples analyzed (78.4%) were found to be positive for C. perfringens spores. Di Bari et al (2007) in São Paulo, Brazil, reported the presence of C. perfringens in 16.5% (103 samples) of the drinkable water sources analyzed. Bonde (1963) suggested that all SRCS in waters are not indicators of fecal pollution and that C. perfringens is the appropriate indicator.…”