Consumption of Tank Rainwater and Influence of Recent Rainfall on the Risk of Gastroenteritis among Young Children in Rural South Australia

Background: The proportion of households that use tank rainwater as their main source of drinking water is similar to the proportion using reticulated public mains supplies in South Australia. However, little is known about risk to health from consuming rainwater. Aims: (1) To determine whether the risk of gastroenteritis among children who drank tank rainwater differed from that of children who drank treated public mains water. (2) To investigate whether recent rainfall affected this risk. Methods: A cohort study of 1,016 fourto six-year-old children who drank rainwater or treated mains water in rural South Australia was undertaken in 1999. Parents kept a daily diary of their child’s gastrointestinal symptoms and water consumption for a period of six weeks. Data on respiratory illness and other risk factors for gastroenteritis were also collected. Results: No increase in risk of gastroenteritis was observed among children who drank rainwater consumption compared with treated mains water. The adjusted odds ratio for gastroenteritis associated with rainwater consumption compared with mains consumption was 0.84 (95% confidence interval: 0.631.13). Conclusions: Young children who were regular consumers of tank rainwater, were at no greater risk of gastroenteritis than those who drank treated public mains water.