Effects of source- versus household contamination of tubewell water on child diarrhea in rural Bangladesh: a randomized controlled trial

PLoS One. 2015 Mar 27;10(3):e0121907. doi: 10.1371/journal.pone.0121907. eCollection 2015.

Abstract

Background: Shallow tubewells are the primary drinking water source for most rural Bangladeshis. Fecal contamination has been detected in tubewells, at low concentrations at the source and at higher levels at the point of use. We conducted a randomized controlled trial to assess whether improving the microbiological quality of tubewell drinking water by household water treatment and safe storage would reduce diarrhea in children <2 years in rural Bangladesh.

Methods: We randomly assigned 1800 households with a child aged 6-18 months (index child) into one of three arms: chlorine plus safe storage, safe storage and control. We followed households with monthly visits for one year to promote the interventions, track their uptake, test participants' source and stored water for fecal contamination, and record caregiver-reported child diarrhea prevalence (primary outcome). To assess reporting bias, we also collected data on health outcomes that are not expected to be impacted by our interventions.

Findings: Both interventions had high uptake. Safe storage, alone or combined with chlorination, reduced heavy contamination of stored water. Compared to controls, diarrhea in index children was reduced by 36% in the chlorine plus safe storage arm (prevalence ratio, PR = 0.64, 0.55-0.73) and 31% in the safe storage arm (PR = 0.69, 0.60-0.80), with no difference between the two intervention arms. One limitation of the study was the non-blinded design with self-reported outcomes. However, the prevalence of health outcomes not expected to be impacted by water interventions did not differ between study arms, suggesting minimal reporting bias.

Conclusions: Safe storage significantly improved drinking water quality at the point of use and reduced child diarrhea in rural Bangladesh. There was no added benefit from combining safe storage with chlorination. Efforts should be undertaken to implement and evaluate long-term efforts for safe water storage in Bangladesh.

Trial registration: ClinicalTrials.gov NCT01350063.

Publication types

  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Bangladesh
  • Diarrhea, Infantile / epidemiology*
  • Diarrhea, Infantile / etiology
  • Diarrhea, Infantile / prevention & control*
  • Drinking Water / microbiology
  • Drinking Water / standards*
  • Halogenation
  • Humans
  • Infant
  • Rural Population
  • Water Purification / methods*
  • Water Quality / standards
  • Water Wells

Substances

  • Drinking Water

Associated data

  • ClinicalTrials.gov/NCT01350063

Grants and funding

This work was funded by the United States Agency for International Development (USAID). *icddr,b acknowledges with gratitude the commitment of USAID to its research efforts. The contents of this manuscript are the sole responsibility of icddr,b and do not necessarily reflect the views of USAID, CDC or the United States Government. *Medentech provided the NaDCC tablets used in the study free of charge. USAID or Medentech had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.