Where's the pump? Associating sporadic enteric disease with drinking water using a geographic information system, in British Columbia, Canada, 1996–2005

Abstract

We investigated whether risk of sporadic enteric disease differs by drinking water source and type using surveillance data and a geographic information system. We performed a cross-sectional analysis, at the individual level, that compared reported cases of enteric disease with drinking water source (surface or ground water) and type (municipal or private). We mapped 814 cases of campylobacteriosis, cryptosporidiosis, giardiasis, salmonellosis and verotoxigenic Escherichia coli infection, in a region of British Columbia, Canada, from 1996 to 2005, and determined the water source and type for each case's residence. Over the 10-year period, the risk of disease was 5.2 times higher for individuals living on land parcels serviced by private wells and 2.3 times higher for individuals living on land parcels serviced by the municipal surface/ground water mixed system, than the municipal ground water system. Rates of sporadic enteric disease potentially differ by drinking water source and type. Geographic information system technology and surveillance data are accessible to local public health authorities and used together are an efficient and affordable way to assess the role of drinking water in sporadic enteric disease.

A spatial analysis of private well water Escherichia coli contamination in southern Ontario

“…Additionally, some of the samples may be from well systems with private treatment systems. However, given the magnitude of the sample size, this should not have a significant impact on the results found and both municipal and treated well water would favour the null hypothesis (Uhlmann et al, 2009).…”

“…There are health implications with consuming compromised water from rural sources (Raina et al, 1999;Said et al, 2003;Uhlmann et al, 2009;Charrois, 2010). Previous studies have focused on chemical contaminants such as nitrate, arsenic and pesticides Rudolph et al, 1998;Benson et al, 2006;Knobeloch et al, 2013) or bacteriological quality without spatial consideration Rudolph et al, 1998;Bacci and Chapman, 2011; Table 3.…”

“…In England and Wales, the incidence rate of intestinal infectious outbreaks in recipients of private water supplies was 35 times that of those receiving public water supplies (Smith et al, 2006). Within Canada, a study in British Columbia found that the risk of enteric disease was 5.2 times higher for individuals living on land serviced by private wells than those who relied upon municipal groundwater systems (Uhlmann et al, 2009).…”

“…Understanding of the endemic water-borne risks associated with private wells and groundwater is currently lacking (Uhlmann et al, 2009). Surveillance of contaminated wells and identification of clusters with a high risk of contamination would allow public health practitioners to better assess and design interventions and aid in the identification of contributing factors leading to contamination.…”

Assessing risk to groundwater quality using an integrated risk framework

“…Water-borne illnesses represent a serious threat to the well-being of groundwater users (Uhlmann et al 2009). This danger spans a range of consequences to the individual, ranging from minor gastrointestinal (GI) irritation to loss of life.…”