National Institute for Water Research, South African Council for Scientific and Industrial Research, Pretoria,
Pages: 14 Published: Jan 1977
Drinking waters obtained from conventional sources and reclaimed wastewater in South Africa have been analyzed for standard bacterial plate count, total coliform bacteria, fecal coliforms, confirmed Escherichia coli, type I, Pseudomonas aeruginosa, fecal streptococci, Clostridium perfringens, Staphylococcus aureus, enteric viruses, and parasite ova. Apart from the standard plate count, waters which were free of coliforms rarely contained any of the other organisms. P. aeruginosa occasionally was isolated from waters with a zero coliform count, and it is suggested that this organism should be included in some routine quality tests. Epidemiological studies on an isolated community, which included periods when drinking water obtained by conventional methods was supplemented with supplies reclaimed from wastewater, indicated that water which conforms to the criteria of nil coliforms and P. aeruginosa/100 ml, a standard plate count of less than 100/1 ml, and no detectable enteric viruses/10 litre will not transmit microbial diseases. Hospital and city sewage, as well as a river and reservoir polluted with secondary treated sewage, contained large numbers of coliforms with transferable (R factor) resistance to one or more of five commonly used antimicrobial drugs. The survival of R+ coliforms and the transfer of resistance during treatment of sewage and in polluted waters indicated that advanced treatment of wastewater will be necessary to protect water resources against these organisms which have potential health significance. It is suggested that specifications limiting R+ bacteria should be included in water quality standards.
bacteria, water, coliform bacteria, health aspects, reclaimed water, resistant bacteria, R factors, hospital effluents, epidemiology, water treatment, coliforms, Clostridia, enterococci, staphylococci, fecal streptococci, enteric viruses, intestinal parasites
Paper ID: STP34827S