UNC Water and Health Conference

Presenter: Habib Yakubu

Periodically, resource-challenged municipal governments in urban areas of low-income countries face decisions on how to set priorities for sanitation investments and focus resources for impact. This is primarily due to their lack of knowledge of existing innovative evidence- based sanitation tools. SaniPath exposure assessment tool evaluates the public health risks from poor sanitation and unsafe fecal sludge management in low-income urban areas. It has been deployed in 43 neighborhoods in 9 cities ; Accra, Ghana; Vellore, India; Maputo, Mozambique; Siem Reap, Cambodia; Dhaka, Bangladesh; Atlanta, United States; Lusaka, Zambia; Kampala, Uganda and Kumasi; Ghana. The most recent shit flows diagram indicates that only an estimated 45% of the fecal sludge is treated. Four neighborhoods of varying geographic and socio economic characteristics were selected for the deployment of the SaniPath tool based on extensive engagement with Kumasi Metropolitan Assembly (KMA). Trained environmental health assistants collected environmental samples and behavior data from multiple pathways in Moshie Zongo, Dakodwom, Fante Newtown and Ahodwo. The nine pathways investigated were; river water, street food, raw produce, drinking water, bathing water, open drain water, soil, public latrines and floodwater. The unit of analysis of the tool is exposure to fecal contamination. Exposure is a measurement of the average amount of E.coli ingested per month (dose) and the percent of the population exposed to fecal contamination per pathway. The most common dominant exposure pathway for children across all the four neighborhoods was open drains. A large percent of the child population was exposed, ranging from 85% to 95% and a high average dose between 10^6 to 10^8 colony forming units (CFU). For adults, the most dominant pathway varied across all the four Page 50 of 56 neighborhoods. Raw produce was the most common dominant pathway in Moshie Zongo, with 78% of the adult population exposed, and a high dose of >10^7. Bathing water was the most dominant pathway in Fante Newtown; with 81% of the population exposed and a high dose of >10^7. Open drains was the most dominant pathway in Ahodwo and Dakodwom with population exposed >61% and high dose values > 10^6. KMA has used this information to take immediate action in two neighborhoods. Firstly, they investigated the source of contamination of a surface water and sanctioned the property owner who had illegally connected directly a shared latrine’s fecal waste into a community river. Secondly, KMA rolled out a school hygiene program to educate primary school students on good hygiene practices within their school compound, in public spaces around open drains and in school toilets. There are other ongoing plans to use the results to inform their sanitation planning, practice and investments. These actions, show that with commitment and access to evidence based sanitation tools, municipal governments in urban areas are capable of using evidence based sanitation tools to prioritize and focus their sanitation investments.

SaniPath Training Hub Evidence to Action
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UNC Water and Health Conference

Presenter: Wolfgang Mairinger

The SaniPath exposure assessment tool compares risks of exposure to fecal contamination in urban environments across multiple exposure pathways. The tool has been deployed in 39 neighborhoods in 8 cities: Accra, Ghana, Vellore, India; Maputo, Mozambique; Siem Reap, Cambodia; Dhaka, Bangladesh; Atlanta, United States; Lusaka, Zambia; and Kampala, Uganda. Ten exposure pathways were investigated (open drains, ocean water, surface water, floodwater, public latrines, soil, bathing water, raw produce, drinking water, and street food) through behavior surveys and environmental sample analyses. Exposure was expressed as monthly dose (average amount of fecal contamination ingested as measured by E. coli colony-forming units [CFU]) and the percent of population exposed to fecal contamination for each pathway. Magnitude of fecal contamination, frequency of exposure behavior, and estimated fecal exposures were compared across pathways, neighborhoods and cities. The most common dominant exposure pathways for adults were raw produce, open drains, and street food and for children were open drains, produce, and floodwater. For produce, the dose was usually very high (>106 CFU/month), and a large percent of the population was exposed (>80%). For street food, average E. coli concentration ranged from 101.3 CFU/serving in one neighborhood in Lusaka, Zambia to 105.5 CFU/serving in one neighborhood in Dhaka, Bangladesh. Exposure to open drains resulted in high doses (>104 CFU/month), but the population exposed varied (5%-92%) even within the same city. Exposure to fecal contamination via floodwater, usually affected a high percent of population (>80%) but had variable doses (102.5- 1010 CFU/month). Both dose and percent of population exposed varied for public latrines and municipal piped water. This information can help city governments choose effective interventions to reduce the risk of exposure to fecal contamination. Widespread risks from contaminated produce and street food within and across cities underscore the link between excreta management and food safety and need for global action.

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UNC Water and Health Conference

Presenter: Sydney Hubbard

Rapid urbanization has led to a sanitation crisis in many low- and middle-income countries (LMIC). Studies of exposure to fecal contamination through different pathways have been conducted in LMICs. However, it is not clear whether exposure to fecal indicators (e.g. E. coli) from these pathways is associated with health outcomes (e.g. infection/illness). In March 2014, SaniPath in collaboration with the Christian Medical College (CMC) of Vellore, India conducted a cross-sectional exposure assessment in Old Town, a dense, urban unplanned settlement in Vellore. A total of 191 samples were collected from open drains, drinking water, public latrines, soil, raw produce, bathing water, child handrinse, and toy feeding spoon rinse and analyzed for E. coli using membrane filtration method. Spatial coordinates were also collected for each sample. From March 2010 - February 2012, the MAL-ED study, a multi-site project examining enteric infections, enteric dysfunction, and growth outcomes, enrolled a birth cohort of 190 children in Old Town, Vellore. At least 16 stool samples were collected from each child over two years of follow up and were tested for multiple bacterial and viral pathogens. Symptomatic illness was recorded. Geospatial data for Old Town, including open drains, water pipe network, open defecation areas, were extracted from shape files provided by CMC. Under the assumption that the urban environment and the exposure behaviors did not change dramatically between the close of the cohort in 2014 and the SaniPath assessment the same year, each child in the MALED study was linked with the closest environmental samples for each sample type from the SaniPath study. Spatial variables like the distance to the closest open defecation site, cumulative open drain/street/waterpipe lengths within a 100-meter radius, and the number of children also enrolled in the cohort within a 100-meter radius were generated. Generalized linear models were used with the bacterial infection rate, viral infection rate, and symptomatic illness rate as outcomes and environmental fecal contamination from different pathways and spatial variables as covariates. E. coli concentration from the closest public latrine and the distance to the closest open defecation site were significant predictors of bacterial infections in children. The sum of the open drain lengths within a 100-meter radius of the child, as well as the sum of street lengths within a 100-meter radius of the child, were significant predictors of viral infections in children. The E. coli concentration of the closest piped water was the only significant predictor of symptomatic illness in children. These preliminary findings that connect health outcomes to environmental exposure pathways and spatial information indicate differential risk factors for bacterial infections, viral infections, and symptomatic enteric illness in children under 2. These results highlight the need for safe excreta management in dense, urban settings to prevent bacterial infections, while contaminated drinking water seems to be a major driver of symptomatic illness in this population. Human congestion, as proxied by summative surrounding street lengths and open drains, is a key risk factor for viral infection.