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Rural households are often dependent on rivers, springs, boreholes or standpipes some distance from their homes for their daily water requirements. Water for drinking and domestic use is consequently stored in containers in-house which are prone to post-collection contamination. The objective of the study was to determine the most likely origin or place of introduction of E. coli associated with post-collection contamination in rural households, by assessing the degree of genetic relatedness of E. coli present in the stored water and other environmental samples. E. coli isolates were obtained using either mFC agar with confirmation of indole production (44 isolates) or Colilert®-18 (52 isolates). Amplified fragment length polymorphism (AFLP) fingerprinting was applied to determine the genetic relatedness of E. coli isolated from in-house storage containers, drinking cups, hand-swab samples, cattle dung and from the source water (spring water). DNA fingerprints of E. coli produced a number of clusters (>85% similarity scores calculated with the cosine coefficient). Identical E. coli genetic patterns were observed at closely linked points within the domestic pathway of water handling, such as between hand-swab and drinking-cup samples, between storage container and source isolates, and between drinking cups, source water and storage containers. The results indicated that AFLP fingerprinting could be applied to determine the genetic relatedness of E. coli isolated from closely linked points within the domestic pathway of water use within a household. However, the high genetic diversity observed for E. coli bacteria isolated from the difffferent water and environmental samples tested in this study, hampered the identification of post collection points of contamination.Keywords: typing, fingerprinting, amplified fragment length polymorphism, E. coli, water quality, genetic relatedness, AFLP

The Working for Water Programme entails the removal of water-consuming alien vegetation and the restoration of low waterconsuming indigenous vegetation. It was implemented in 1995 to address the management of catchment areas in South Africa. The question of this programme\'s economic feasibility in the Western Cape and in KwaZulu-Natal has been addressed by various authors. This paper addresses its feasibility in the Eastern Cape Province and regions of the southern Cape. Cost-benefit analyses are carried out on six sites: Tsitsikamma, Kouga, Port Elizabeth Driftsands, Albany, Kat River and Pott River. It is shown that catchment management on all the sites carried out by the Working for Water Programme is inefficient. This conclusion is subject to three qualifications. The first is that more work remains to be done on the evaluation of the nonwater benefits. Known non-water benefits, like fire damage reduction and preservation of biodiversity were not included in the calculations. The second qualification is that at lower discount rates, for instance 5%, the Kouga project is efficient. The third qualification is that if 30% cost savings could be achieved and a discount rate of 5% be employed, both the projects on the Kouga and Tsitsikamma sites will become efficient. These two projects are being run in catchments which serve areas where high consumptive demand exists. WaterSA Vol.30 (2) 2004: 143-152

A rapid and sensitive assay was developed for the detection of low numbers of viable Vibrio cholerae and Shigella spp. cells in environmental and drinking water samples. Water samples were filtered, and the filters were enriched in a non-selective medium. The enrichment cultures were prepared for polymerase chain reactions (PCR) by a rapid and simple DNA extraction procedure consisting of boiling. Seminested PCR, based on specific amplification of the cholera toxin operon of V. cholerae and the invasion plasmid antigen gene (ipaH) of virulent Shigella spp., was performed and the PCR products were visualised by agarose gel electrophoresis. The assay allowed the detection of as few as 1 cfu/100 ml of V. cholerae and 8 cfu/100 ml of Shigella cells. A comparison of the PCR method and culturing methods by using environmental water samples showed that the PCR method has a higher level of sensitivity than culturing methods. As an application of the PCR detection protocol, environmental water samples were screened for the presence of V. cholerae and Shigella spp. Positive amplifications resulted from V. cholerae and Shigella species in environmental samples. The results obtained indicate that the described seminested PCR has the advantage of a rapid turn-around time and fulfils the requirements of sensitivity for use in an environmental laboratory. Keywords: Vibrio cholerae, Shigella, Water-borne pathogens, Polymerase chain reaction, Environmental waters, Drinking water, Detection (WaterSA: 2003 29(2): 177-182)