Decentralized water purification using membrane filtration reduces the incidence of diarrhea in communities in developing countries.

Jochen G. Raimann, Joseph Marfo Boaheng, Philip Narh, Seth Johnson, Linda Donald, Hongbin Zhang, Nathan W. Levin

Background

In rural communities in regions with limited resources the provision of clean water remains difficult. The only water available is that from rain collection, wells, streams and lakes. Fecal contamination of water is very common and results in a high incidence of diarrhea, subsequent acute kidney injury and mortality particularly in the very young and old. Membrane filtration is a practical solution to this problem and recent innovation allows membrane filtration using recycled dialyzers. We, Easy Water for Everyone, have attempted to quantify the systematic effect on health outcomes by providing clean water using a high-volume membrane filtration device with recycled dialyzers.

Methods

Between 06/2015 and 12/2018, 17 communities in rural Ghana (Ashanti-Ghana and Greater-Accra region; village size ranging in size from 5 to 591 people) were provided with high-volume membrane filtration devices (NUF 500; NuFiltration using recycled dialyzers). Health data from household surveys and chart review in local healthcare facilities were collected with approval from Ghana Health Services. Specifically, data was collected on gastrointestinal disease, acute kidney injury and therapeutic interventions. Further data on demographics, village and community characteristics and other potentially relevant aspects were also collected. Incidence rates for 6 months periods before and after implementation of the device were calculated.

Results

Data from 3611 villagers over 17 months from the 12 studied communities in rural Ghana (around 13% 5 years or younger and 6% older than 65 years) were included in this analysis. The overall incidence rate of diarrhea showed a declining trend following the implementation of the filtration device in the village structure and was reduced from 1.5 to 0.8 cases per 1000 person days from the before to the after period (Figure 1). A formal comparison of the rate reduction and detailed multi-level time-series analyses are currently underway.

Discussion

Provision of a membrane filtration device has the potential of significant improvements of health outcomes within rural communities. While our data requires a larger sample size and further statistical analyses accounting for village characteristics, seasonality and subject demographics, the obvious decline in incidence rates supports widespread use of membrane filtration devices, particularly in rural regions. Next to multi-level longitudinal analyses, future studies from our group will include an approach using a stepped-wedge cluster randomized design for the rollout of the device in further sites which will even further increase our understanding in terms of risk and preventive factors modifying the incidence of diarrhea and subsequent acute kidney injury