title: Contaminated small drinking water supplies and risk of infectious intestinal disease: a prospective cohort study.
abstract: BACKGROUND
  This study sought to identify whether elevated risk of infectious intestinal disease (IID) exists in contaminated small water supply consumers compared with consumers drinking from small supplies complying with current standards and whether this effect is modified by age.
  
  
  RESULTS
  A prospective cohort study of 611 individuals receiving small supplies in England was conducted. Water supplies received sanitary inspection and examination for indicator bacteria and participants maintained a daily record of IID. Regression modeling with generalized estimating equations that included interaction terms between age and indicators of fecal pollution was performed. Crude IID prevalence was 9 · 3 days with symptoms/1000 person days (95%CI: 8 · 4, 10 · 1) and incidence was 3 · 2 episodes/1000 person days (95%CI, 2 · 7, 3 · 7) or 1 · 2 episodes per person year. Although there was no overall association between IID risk and indicator presence, there was strong interaction between age and indicator presence. In children under ten, relative risk (RR) of IID in those drinking from enterococci contaminated supplies was 4.8 (95%CI: 1.5, 15.3) for incidence and 8.9 (95%CI: 2.8, 27.5) for prevalence. In those aged 10 to 59, IID risk was lower but not statistically significant.
  
  
  CONCLUSIONS
  Contaminated small water supplies pose a substantial risk of IID to young children who live in homes reliant on these supplies. By contrast older children and adults do not appear to be at increased risk. Health care professionals with responsibility for children living in homes provided by very small water supplies should make parents aware of the risk.
authors.affiliation: Norwich Medical School, University of East Anglia, Norwich, United Kingdom.
authors.forename: Helen L
authors.initials: HL
authors.lastname: Risebro
authors.forename: Lynette
authors.initials: L
authors.lastname: Breton
authors.forename: Heather
authors.initials: H
authors.lastname: Aird
authors.forename: Alan
authors.initials: A
authors.lastname: Hooper
authors.forename: Paul R
authors.initials: PR
authors.lastname: Hunter
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D002648:Child; D003141:Communicable Diseases / Q000453:epidemiology* / Q000209:etiology; D060766:Drinking Water / Q000469:parasitology*; D004739:England; D005260:Female; D006801:Humans; D015994:Incidence; D007410:Intestinal Diseases / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D060766:Drinking Water