A study was undertaken in Njoro Township, Kenya to evaluate the extent to which drinking water was subjected to post-collection faecal contamination in low-income and high-income households. Boreholes were the main drinking water sources, accounting for roughly 70% singular access. The microbial quality of drinking water from the boreholes deteriorated from the point-of-collection through conveying containers of small-scale water vendors to household storage containers, irrespective of their income status. The densities of Escherichia coli (EC) were relatively low at the point-of-collection – median (M): 18 CFU/100 mL, range (R): 0–220, n = 60 – increasing considerably in the containers of water vendors (M: 290 CFU/100 mL, R: 30–350) and slightly (M: 360 CFU/100 mL, R: 0–520) between vendors and low-income households, many of whom used the services of vendors unlike high-income households who relied on a piped system on premises (M: 40 CFU/100 mL, R: 0–500). Post-collection contamination was high in low-income households compared to high-income households but differences were not significant between the two household categories with and without household water treatment (HWT). Different HWT methods in the two household categories significantly reduced faecal contamination, but unhygienic handling and poor storage practices afterwards caused recontamination. HWT and behavioural change measures need not selectively target household groups solely on the basis of their income status.

Between January and December 1999 the extent of biofilm development has been studied at two sites (muddy sediment site [A] and sandy sediment site [B]) in Njoro River, Kenya. Grain size, organic matter and bacterial abundance were determined at different depth layers of the sediment. Particulate carbohydrate concentrations were measured as an indicator of biofilm development in the sediment. Additionally, the development of the biofilm was investigated by placing glass slides at rock and sediment surfaces and in different sediment depth layers. Our first results for sediment samples collected in January 1999 and growth on slides exposed for 28 days in March 1999 is presented. Grain size analysis revealed that sediment particles <1 mm contributed between 82 to 91% at site A and 45 to 67% at site B depending on the sediment layer. At site A, total organic matter (% weight loss on ignition) and total organic carbon (TOC) were more or less constant with depth while both parameters significantly decreased with depth at site B. Total organic nitrogen (TON) was detectable at all depth layers at site A but only in the top 40 mm layer at site B. Bacterial numbers were highest in the top 40 mm layer at both sites. Bacterial abundance of 3.95 ± 5.96 × 10 8 and 4.10 ± 3.88 × 10 8 cells g -1 dry sediment were recorded at site A and B, respectively. For both sites, highest concentrations of colloidal carbohydrates occurred in the top 40 mm layer, but concentrations were more or less constant below. Bacterial abundance on glass slides was higher on slides placed on rock surfaces than on fine sediment surfaces or within fine sediments.

cases and 210 controls) were analysed regarding phenotypic characteristics for risk of melanoma as well as number of grandparents born in Europe. European ancestry (Spanish, Italian, Germanic or Slavic, and 2 or more European country), eye colour (light brown and green or blue), presence of nevi, use of sunscreen, referred episodes of sunburn in adolescence or not, were independently associated with melanoma. Portuguese ancestry was not associated in multivariate logistic regression analysis. Our data confirmed the importance of European ancestry as a susceptibility factor. The higher tendency to develop melanoma in persons with those ancestries could be related not only to the phenotypic but probably also to other genetic characteristics. Case-patients for a retrospective epidemiological cum microbiological study in Njoro Town, Kenya were selected after self-report of waterborne illness within 7 days of exposure through drinking water. Controls were matched for location, household income and type of drinking water source. Households with piped water in one highincome district reported considerably lower illness rates compared to unconnected households in two low-income districts. Analysis of the ORs identified water from the stream to be associated with the highest risk of illness (OR¼3.95, p¼0.03) compared to untreated rainwater (OR¼2.45, p¼0.02), untreated water from boreholes (OR¼1.90, p¼0.02) or treated water from any source (OR¼0.62, p¼0.01). Bacteria densities in water obtained from the stream were generally 1e3 log units higher compared to other sources, staying within 3e4 log units for HPC (cfu/ml) and TC (cfu/100 ml), 2e3 log units (cfu/ 100 ml) for Escherichia coli and intestinal enterococci and within 1 log unit (cfu/100 ml) for Salmonella. Several confounding risk factors other than contaminated water were identified. Their detection for over 50 % of all illness cases was significant. It was concluded that the importance of drinking water quality as the most likely source of endemic waterborne illness in the community may have been previously overestimated. Therefore, interventions on water supply in the town should include strategies that address confounding risk factors, especially, poor hygiene and occupational hazards, as well as piped water distribution to low-income households. Objectives To study the magnitude and determinants of growth faltering among 0e6 year 's children in adopted villages of rural medical college. Material and Methods A total 305 children of <6 years were followed monthly for 1 year to assess the growth faltering. At each visit, the mothers/caretaker of children were interviewed and information regarding immunisation, morbidity profile, dietary history and child feeding practices collected using a pre-tested interview schedule. Monthly anthropometric measurements of child were taken. P2-443 P2-444Growth faltering has been defined as failure to gain weight or actual loss of weight, and weight gain <300 g over a period of three consecutive months. Results The cumulative inc...

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Constructed wetlands (CWs) polish wastewater prior to discharge into aquatic receptacles. Size variabilities of substrates used in CWS may have effects on the treatment efficiencies though there is scanty information regarding this aspect in VSSF CWs. To address this knowledge gap, a laboratory scale mesocosm experiment was set up to investigate the potential of a VSSF CW to reduce organic matter and FIB using various gravel substrate aggregate sizes. These consisted of three gravel size treatment units; <12.5, 12.5-18 and 18-24 mm in triplicates. 70 liters of pre-treated wastewater from final wastewater stabilization pond (WSP) of Egerton University’s WSPs was added to the units, allowed to settle for 6 weeks for development of biofilms, followed by periodic feeding of equal wastewater quantity on weekly basis and influent and effluent samples collected for 8 weeks for analysis.  Results disclosed reduction efficiency of 95.2, 94.3 and 88.4 % for E coli in the fine, medium and coarse gravel aggregates respectively. Less than 20 % reduction efficiency was recorded for BOD5 in all gravel aggregate sizes. There was no significant variation on performance of the three gravel aggregate sizes in reduction of both FIB and BOD5 (p˃0.05). Poor performance in BOD5 reduction was related to absence of wetland macrophytes in the study. The relatively high reduction efficiency for FIB was attributed to other factors and processes such as predation, mechanical interactions, starvation, microbial interactions and natural die-offs. The study recommends assessing the combined effort of wetland macrophytes, increased hydraulic retention time and substrates.