Bacterial, viral and turbidity removal by intermittent slow sand filtration for household use in developing countries: experimental investigation and modeling.

A two-factor three-block experimental design was developed to permit rigorous evaluation and modeling of the main effects and interactions of sand size (d(10) of 0.17 and 0.52 mm) and hydraulic head (10, 20, and 30 cm) on removal of fecal coliform (FC) bacteria, MS2 bacteriophage virus, and turbidity, under two batch operating modes ('long' and 'short') in intermittent slow sand filters (ISSFs).

Identifying human and livestock sources of fecal contamination in Kenya with host-specific Bacteroidales assays.

Microbial source tracking to distinguish between human, livestock and wildlife fecal pollution using molecular techniques is a rapidly evolving approach in many developed countries, but has not previously been applied on the African continent. DNA extracts from cow, donkey, and human fecal specimens and raw domestic sewage samples collected in Kenya were tested against five existing quantitative PCR assays designed to detect universal (2), human-specific (2), and cow-specific (1) fecal Bacteroidales genetic markers. Water samples from the River Njoro in Kenya were evaluated using the five tested Bacteroidales markers and a multi-species assay for Cryptosporidium in a preliminary exploration of fecal pollution sources and health risks in this watershed.