Skip to main content
Environmental Health Perspectives logoLink to Environmental Health Perspectives
. 2001 Aug;109(8):773–778. doi: 10.1289/ehp.01109773

A randomized, blinded, controlled trial investigating the gastrointestinal health effects of drinking water quality.

M E Hellard 1, M I Sinclair 1, A B Forbes 1, C K Fairley 1
PMCID: PMC1240403  PMID: 11564611

Abstract

A double-blinded, randomized, controlled trial was carried out in in Melbourne, Australia, to determine the contribution of drinking water to gastroenteritis. Melbourne is one of the few major cities in the world that draws drinking water from a protected forest catchment with minimal water treatment (chlorination only). Six hundred families were randomly allocated to receive either real or sham water treatment units (WTUs) installed in their kitchen. Real units were designed to remove viruses, bacteria, and protozoa. Study participants completed a weekly health diary reporting gastrointestinal symptoms during the 68-week observation period. There were 2,669 cases of highly credible gastroenteritis (HCG) during the study (0.80 cases/person/year). The ratio of HCG episode rates for the real WTU group compared to the sham WTU group was 0.99 (95% confidence interval, 0.85-1.15, p = 0.85). We collected 795 fecal specimens from participants with gastroenteritis, and pathogens were not more significantly common in the sham WTU group. We found no evidence of waterborne disease in Melbourne. The application of this methodology to other water supplies will provide a better understanding of the relationship between human health and water quality.

Full Text

The Full Text of this article is available as a PDF (88.6 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Byington R. P., Curb J. D., Mattson M. E. Assessment of double-blindness at the conclusion of the beta-Blocker Heart Attack Trial. JAMA. 1985 Mar 22;253(12):1733–1736. [PubMed] [Google Scholar]
  2. Eyers M., Chapelle S., Van Camp G., Goossens H., De Wachter R. Discrimination among thermophilic Campylobacter species by polymerase chain reaction amplification of 23S rRNA gene fragments. J Clin Microbiol. 1993 Dec;31(12):3340–3343. doi: 10.1128/jcm.31.12.3340-3343.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Furtado C., Adak G. K., Stuart J. M., Wall P. G., Evans H. S., Casemore D. P. Outbreaks of waterborne infectious intestinal disease in England and Wales, 1992-5. Epidemiol Infect. 1998 Aug;121(1):109–119. doi: 10.1017/s0950268898001083. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Hellard M. E., Sinclair M. I., Fairley C. K., Andrews R. M., Bailey M., Black J., Dharmage S. C., Kirk M. D. An outbreak of cryptosporidiosis in an urban swimming pool: why are such outbreaks difficult to detect? Aust N Z J Public Health. 2000 Jun;24(3):272–275. doi: 10.1111/j.1467-842x.2000.tb01567.x. [DOI] [PubMed] [Google Scholar]
  5. Hellard M. E., Sinclair M. I., Hogg G. G., Fairley C. K. Prevalence of enteric pathogens among community based asymptomatic individuals. J Gastroenterol Hepatol. 2000 Mar;15(3):290–293. doi: 10.1046/j.1440-1746.2000.02089.x. [DOI] [PubMed] [Google Scholar]
  6. James K. E., Bloch D. A., Lee K. K., Kraemer H. C., Fuller R. K. An index for assessing blindness in a multi-centre clinical trial: disulfiram for alcohol cessation--a VA cooperative study. Stat Med. 1996 Jul 15;15(13):1421–1434. doi: 10.1002/(SICI)1097-0258(19960715)15:13<1421::AID-SIM266>3.0.CO;2-H. [DOI] [PubMed] [Google Scholar]
  7. Kaucner C., Stinear T. Sensitive and rapid detection of viable Giardia cysts and Cryptosporidium parvum oocysts in large-volume water samples with wound fiberglass cartridge filters and reverse transcription-PCR. Appl Environ Microbiol. 1998 May;64(5):1743–1749. doi: 10.1128/aem.64.5.1743-1749.1998. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Mac Kenzie W. R., Hoxie N. J., Proctor M. E., Gradus M. S., Blair K. A., Peterson D. E., Kazmierczak J. J., Addiss D. G., Fox K. R., Rose J. B. A massive outbreak in Milwaukee of cryptosporidium infection transmitted through the public water supply. N Engl J Med. 1994 Jul 21;331(3):161–167. doi: 10.1056/NEJM199407213310304. [DOI] [PubMed] [Google Scholar]
  9. Mahbubani M. H., Bej A. K., Perlin M., Schaefer F. W., 3rd, Jakubowski W., Atlas R. M. Detection of Giardia cysts by using the polymerase chain reaction and distinguishing live from dead cysts. Appl Environ Microbiol. 1991 Dec;57(12):3456–3461. doi: 10.1128/aem.57.12.3456-3461.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Mead P. S., Slutsker L., Dietz V., McCaig L. F., Bresee J. S., Shapiro C., Griffin P. M., Tauxe R. V. Food-related illness and death in the United States. Emerg Infect Dis. 1999 Sep-Oct;5(5):607–625. doi: 10.3201/eid0505.990502. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Noseworthy J. H., Ebers G. C., Vandervoort M. K., Farquhar R. E., Yetisir E., Roberts R. The impact of blinding on the results of a randomized, placebo-controlled multiple sclerosis clinical trial. Neurology. 1994 Jan;44(1):16–20. doi: 10.1212/wnl.44.1.16. [DOI] [PubMed] [Google Scholar]
  12. Paton A. W., Paton J. C. Detection and characterization of Shiga toxigenic Escherichia coli by using multiplex PCR assays for stx1, stx2, eaeA, enterohemorrhagic E. coli hlyA, rfbO111, and rfbO157. J Clin Microbiol. 1998 Feb;36(2):598–602. doi: 10.1128/jcm.36.2.598-602.1998. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Payment P., Richardson L., Siemiatycki J., Dewar R., Edwardes M., Franco E. A randomized trial to evaluate the risk of gastrointestinal disease due to consumption of drinking water meeting current microbiological standards. Am J Public Health. 1991 Jun;81(6):703–708. doi: 10.2105/ajph.81.6.703. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Stinear T., Matusan A., Hines K., Sandery M. Detection of a single viable Cryptosporidium parvum oocyst in environmental water concentrates by reverse transcription-PCR. Appl Environ Microbiol. 1996 Sep;62(9):3385–3390. doi: 10.1128/aem.62.9.3385-3390.1996. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Willocks L., Crampin A., Milne L., Seng C., Susman M., Gair R., Moulsdale M., Shafi S., Wall R., Wiggins R. A large outbreak of cryptosporidiosis associated with a public water supply from a deep chalk borehole. Outbreak Investigation Team. Commun Dis Public Health. 1998 Dec;1(4):239–243. [PubMed] [Google Scholar]
  16. Zmirou D., Ferley J. P., Collin J. F., Charrel M., Berlin J. A follow-up study of gastro-intestinal diseases related to bacteriologically substandard drinking water. Am J Public Health. 1987 May;77(5):582–584. doi: 10.2105/ajph.77.5.582. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Environmental Health Perspectives are provided here courtesy of National Institute of Environmental Health Sciences

RESOURCES