DRINKING-WATER TURBIDITY AND PEDIATRIC HOSPITAL USE FOR GASTROINTESTINAL ILLNESS IN PHILADELPHIA

Recent outbreaks have demonstrated that serious infectious gastrointes tinal illness related to drinking water supplies remains a problem in the United States. The magnitude is unknown, but children, the elderly , and immunocompromised individuals are considered at highest risk. We examined the association between daily measures of drinking water tur bidity and both emergency visits and admissions to Children's Hospital of Philadelphia for gastrointestinal illness, controlling for time tr ends, seasonal patterns, and temperature. We found that an interquarti le range increase in turbidity levels in Philadelphia drinking water w as associated with a 9.9% increase [95% confidence limits (CL) = 2.9%, 17.3%] in gastrointestinal emergency visits for children age 3 years and older 4 days later. For children age 2 years and younger, an assoc iation was found with a lag of 10 days (5.9% increase; 95% CL = 0.2, 1 2.0). For admissions, a similar pattern was seen. For children over 2 years old, an increase of 31.1% (95% CL = 10.8%, 55%) was seen with a lag of 5-6 days. For younger children, an increase of 13.1% (95% CL = 3.0, 24.3) was seen 13 days later. This association occurred in a filt ered water supply in compliance with current federal standards.