Drinking water turbidity and gastrointestinal illness in the elderly of Philadelphia

Abstract

Study objective-To investigate the association between drinking water quality and gastrointestinal illness in the elderly of Philadelphia. Design-Within the general population, children and the elderly are at highest risk for gastrointestinal disease. This study investigates the potential association between daily fluctuations in drinking water turbidity and subsequent hospital admissions for gastrointestinal illness of elderly persons, controlling for time trends, seasonal patterns, and temperature using Poisson regression analysis. Setting and participants-All residents of Philadelphia aged 65 and older in 1992-1993 were studied through their MEDI-CARE records. Main results-For Philadelphia's population aged 65 and older, we found water quality 9 to 11 days before the visit was associated with hospital admissions for gastrointestinal illness, with an interquartile range increase in turbidity being associated with a 9% increase (95% CI 5.3%, 12.7%). In the Belmont service area, there was also an association evident at a lag of 4 to 6 days (9.1% increase, 95% CI 5.2, 13.3). Both associations were stronger in those over 75 than in the population aged 65-74. This association occurred in a filtered water supply in compliance with US standards. Conclusions-Elderly residents of Philadelphia remain at risk of waterborne gastrointestinal illness under current water treatment practices. Hospitalisations represent a very small percentage of total morbidity. (J Epidemiol Community Health 2000;54:45-51)

U.S. drinking water challenges in the twenty-first century.

“…Current incidence estimates are three to four orders of magnitude higher than the CDC data (77-79). Empirical evidence from a variety of water systems meeting federal drinking water standards suggests that 6-40% of gastrointestinal illness in the United States may be water related (74)(75)(76)(80)(81)(82); recent data from Canada present a similar picture there (83).…”

“…A complication of drinking water disinfection is the emerging evidence of carcinogenic and possibly other health effects associated with disinfection by-products (DBPs) such as trihalomethanes (THMs) (74,76,(80)(81)(82). Nonetheless, we believe that the new evidence of carcinogenic and other health effects from exposure to disinfected water cannot be ignored and will likely challenge the public health and water utility communities in the twenty-first century.…”

Seasonality of Infectious Diseases

“…If several events can be expected on a daily basis, time-series models based on a Poisson distribution may provide important insight into factors driving event occurrence. For example, Schwartz and colleagues (71,72) used such an approach to document the close relationship between drinking water turbidity and diarrhea-related emergency room visits in Philadelphia; a similar approach taken by Aramini and colleagues (8) in Vancouver identified a similar relationship (Figure 7). This approach can be modified when the outcome of interest is a surge in disease activity rather than absolute case numbers, as Teklehaimot and colleagues have done in their work linking climatic conditions to acute surges in malaria cases (80,81).…”

Supply system factors associated with microbiological drinking water safety in regional New South Wales, Australia, 2001–2007

“…Even in filtered supplies fluctuations in turbidity have been associated with an increase in gastrointestinal illness (Schwartz et al 1997(Schwartz et al , 2000.…”