a1 Department of Paediatrics, Medical College of Wisconsin, Milwaukee, WI, USA
a2 Department of Population Health, Medical College of Wisconsin, Milwaukee, WI, USA
a3 Children's Research Institute, Milwaukee, WI, USA
a4 Great Lakes WATER Institute, University of Wisconsin – Milwaukee, Milwaukee, WI, USA
We examined the association between water exposures and acute diarrhoeal illness (ADI) in children under non-outbreak conditions in a major US metropolitan area. We used a nested case-control study of children seen in an urban/suburban emergency department. Cases were those seen for a complaint of diarrhoea, while controls were age-matched children with a non-gastrointestinal complaint. Parents of subjects completed a validated water-use survey. Stratum-specific adjusted odds ratios (aOR) were calculated for the three main water effects: water source [surface vs. ground (well)], drinking-water type (tap vs. bottled), and use of water filters. Of 2472 subjects, 45% drank mostly or only bottled water. Well-water use was associated with increased odds of ADI compared to surface water [aOR 1·38, 95% confidence interval (CI) 1·01–1·87]. Use of bottled water did not affect the odds of ADI in well-water users, but increased the odds of ADI for surface-water users (aOR 1·27, 95% CI 1·02–1·57). We conclude that well-water use and bottled-water use are associated with increased odds of ADI in children.
(Accepted March 17 2010)
(Online publication April 30 2010)