Quantification of exposure to fecal contamination in open drains in four neighborhoods in Accra, Ghana
Authors: Stephanie R. Gretsch, Joseph A. Ampofo, Kelly K. Baker, Julie Clennon, Clair A. Null, Dorothy Peprah, Heather Reese, Katharine Robb, Peter Teunis, Nii Wellington, Habib Yakubu, Christine L. Moe
Abstract: In low-income countries, rapid urbanization adds pressure to already stressed water and sanitation systems that are critical to the health of communities. Drainage networks, designed for stormwater but commonly used for disposing of waste, are rarely covered completely, allowing residents to easily contact their contents. This study used spatial mapping, documentation of physical drain characteristics, microbiological analysis of drain samples, and behavioral observation to comprehensively examine drains as a route of exposure to fecal contamination in four low-income neighborhoods in Accra, Ghana. A stochastic model of six likely exposure scenarios was constructed to estimate children’s exposure to drain water. Regardless of the age of the child, any exposure scenario considered resulted in exposure to a high level of fecal contamination. Fecal contamination levels in drains were high (E. coli: geometric mean (GM), 8.60 cfu log10/100 mL; coliphage: GM, 5.56 pfu log10/100 mL), and did not differ by neighborhood or physical drain characteristics, indicating that frequency of contact with drains, and not drain type or location, drives exposure risk. To mitigate health risks associated with this exposure, drains should be covered, with priority given to large concrete and small to medium dirt-lined drains that children were most commonly observed entering.