1921
Volume 96, Issue 4
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645

Abstract

Abstract

The use of sanitary inspections combined with periodic water quality testing has been recommended in some cases as screening tools for fecal contamination. We conducted sanitary inspections and tested for thermotolerant coliforms (TTCs), a fecal indicator bacteria, among 7,317 unique water sources in West Bengal, India. Our results indicate that the sanitary inspection score has poor ability to identify TTC-contaminated sources. Among deep and shallow hand pumps, the area under curve (AUC) for prediction of TTC > 0 was 0.58 (95% confidence interval [CI] = 0.53–0.61) and 0.58 (95% CI = 0.54–0.62), respectively, indicating that the sanitary inspection score was only marginally better than chance in discriminating between contaminated and uncontaminated sources of this type. A slightly higher AUC value of 0.64 (95% CI=0.57–0.71) was observed when the sanitary inspection score was used for prediction of TTC > 0 among the gravity-fed piped sources. Among unprotected springs (AUC = 0.48, 95% CI = 0.38–0.55) and unprotected dug wells (AUC = 0.41, 95% CI = 0.20–0.66), the sanitary inspection score performed more poorly than chance in discriminating between sites with TTC < 1 and TTC > 0. Aggregating over all source types, the sensitivity (true positive rate) of a high/very high sanitary inspection score for TTC contamination (TTC > 1 CFU/100 mL) was 29.4% and the specificity (true negative rate) was 77.9%, resulting in substantial misclassification of the sites when using the established risk categories. These findings suggest that sanitary surveys are inappropriate screening tools for identifying TTC contamination at water points.

Loading

Article metrics loading...

The graphs shown below represent data from March 2017
/content/journals/10.4269/ajtmh.16-0322
2017-04-05
2018-12-19
Loading full text...

Full text loading...

/deliver/fulltext/14761645/96/4/976.html?itemId=/content/journals/10.4269/ajtmh.16-0322&mimeType=html&fmt=ahah

References

  1. World Health Organization, 2015. Drinking Water, Fact sheet no. 391. Available at: http://www.who.int/mediacentre/factsheets/fs391/en/. Accessed September 5, 2015. [Google Scholar]
  2. Central Bureau of Health Intelligence, Directorate General of Health Services, Ministry of Health and Family Welfare, 2013. National Health Profile 2013. New Delhi, India: Government of India. [Google Scholar]
  3. UNICEF/WHO, 2009. Diarrhoea: Why Children Are Still Dying and What Can Be Done. Geneva, Switzerland: WHO. [Google Scholar]
  4. Hodge J, Chang HH, Boisson S, Collin SM, Peletz R, Clasen T, , 2016. Assessing the association between thermotolerant coliforms in drinking water and diarrhea: an analysis of individual level data from multiple studies. Environ Health Perspect, doi: 10.1289/EHP156. [Google Scholar]
  5. Fewetrell L, Kauffman R, Kay D, Enanoria W, Haller L, Colford J, , 2005. Water, sanitation, and hygiene interventions to reduce diarrhea in less developed countries: a systematic review and meta-analysis. Lancet 5: 4252.[Crossref] [Google Scholar]
  6. Wisner B, Adams J, , 2003. Environmental Health in Emergencies and Disasters: A Practical Guide. Geneva, Switzerland: World Health Organization. [Google Scholar]
  7. Lloyd BJ, Helmer R, , 1991. Surveillance of Drinking Water Quality in Rural Areas. New York, NY: Logman Scientific and Technical, Co-published in the United States with John Wiley and Sons, Inc. [Google Scholar]
  8. WHO, 1993. Guidelines for Drinking-Water Quality, Vol. 1: Recommendation, 2nd edition. Geneva, Switzerland: World Health Organisation. [Google Scholar]
  9. Lloyd BJ, Bartram JK, , 1991. Surveillance solutions to microbiological problems in water quality control in developing countries. J Water Science Technol 24: 6175. [Google Scholar]
  10. WHO, 1997. Guidelines for Drinking-Water Quality, Vol. 3: Surveillance and Control of Community Supplies, 2nd edition. Geneva, Switzerland: World Health Organization. [Google Scholar]
  11. ARGOSS, 2001. Guidelines for Assessing the Risk to Groundwater from On-Site Sanitation. Swindon, United Kingdom: British Geological Survey Commissioned Report, CR/01/142, 97. Available at: http://www.susana.org/_resources/documents/default/2-1926-argoss-manual.pdf. [Google Scholar]
  12. Luby S, Gupta S, Sheikh M, Johnston R, Ram R, Islam S, , 2008. Tubewell water quality and predictors of contamination in three flood-prone areas in Bangladesh. J Appl Microbiol 105: 10021008.[Crossref] [Google Scholar]
  13. Barthiban S, Lloyd B, Maier M, , 2012. Sanitary hazards and microbial quality of open dug wells in the Maldives Islands. J Water Resource Prot 4: 474486.[Crossref] [Google Scholar]
  14. Mushi D, Byamukama D, Kirscher A, Mach R, Brunner K, Farnleitner A, , 2012. Sanitary inspection of wells using risk-of-contamination scoring indicates a high predictive ability for bacterial faecal pollution in the peri-urban tropical lowlands of Dar es Salaam, Tanzania. J Water Health 10: 236243.[Crossref] [Google Scholar]
  15. Parker A, Youlten R, Dillon D, Nussbaumer T, Carter R, Tyrell S, Webster J, , 2010. An assessment of microbiological water quality of six water source categories in north-east Uganda. J Water Health 8: 550560.[Crossref] [Google Scholar]
  16. Howard G, Pedley S, Barrett M, Nalubega M, Johal K, , 2003. Risk factors contributing to microbiological contamination of shallow ground water in Kampala, Uganda. Water Res 37: 34213429.[Crossref] [Google Scholar]
  17. Lloyd BJ, Boonyakarnkul T, , 1991. Combined Assessment of Sanitary Hazards and Faecal Coliform Intensity for Rural Groundwater Supply Improvement in Thailand. National conference on Geologic Resources of Thailand: Potential for Future Development. November 17–24, 1992. Department of Mineral Resources, Bangkok, Thailand. [Google Scholar]
  18. Ministry of Drinking Water and Sanitation, Government of India, 2013. Uniform Drinking Water Quality Monitoring Protocol. New Delhi, India: s.n. Ministry Of Drinking Water And Sanitation, Government Of India. [Google Scholar]
  19. Bureau of Indian Standards, 1981. Methods of Sampling and Microbiological Examination of Water (First Revision). IS 1622. New Delhi, India: s.n. Bureau of Indian Standards. [Google Scholar]
  20. Byamukama D, Mach RL, Kansiime F, Manafi M, Farnleitner AH, , 2005. Discrimination efficacy of faecal pollution detection in different aquatic habitats of a high altitude tropical country using presumptive coliform, Escherichia coli and Clostridium perfringes spores. Appl Environ Microbiol 71: 6571.[Crossref] [Google Scholar]
  21. Solo-Gabriele HM, Wolfert MA, Desmarais TR, Palmer CJ, , 2000. Sources of Escherichia coli in a coastal subtropical environment. Appl Environ Microbiol 66: 230237.[Crossref] [Google Scholar]
  22. Ishii S, Sadowsky MJ, , 2008. Escherichia coli in the environment: implications for water quality. Microbes Environ 23: 101108.[Crossref] [Google Scholar]
  23. WHO, 1996. Guidelines for Drinking-Water Quality, Vol. 2: Health and Supporting Criteria, 2nd edition. Geneva, Switzerland: World Health Organization. [Google Scholar]
  24. Zou KH, O'Malley AJ, Mauri L, , 2007. Receiver-operating characteristic analysis for evaluating diagnostic tests and predictive models. Circulation 115: 654657.[Crossref] [Google Scholar]
  25. Alonzo TA, Pepe MS, , 2002. Distribution-free ROC analysis using binary regression techniques. Biostatistics 3: 421432.[Crossref] [Google Scholar]
  26. Colak E, Mutlu F, Bal C, Oner S, Ozdamar K, Gok B, Cavusoglu Y, , 2012. Comparison of semiparametric, parametric, and nonparametric ROC analysis for continuous diagnostic tests using a simulation study and acute coronary syndrome data. Comput Math Methods Med 2012: 2012.[Crossref] [Google Scholar]
  27. Ware JH, , 2006. The limitations of risk factors as prognostic tools. N Engl J Med 355: 26152617.[Crossref] [Google Scholar]
  28. Pepe MS, Janes H, Longton G, Leisenring W, Newcomb P, , 2004. Limitations of the odds ratio in gauging the performance of a diagnostic, prognostic, or screening marker. Am J Epidemiol 159: 882890.[Crossref] [Google Scholar]
  29. Bain R, Cronk R, Wright J, Yang H, Skaymaker T, Bartram J, , 2014. Fecal contamination of drinking-water in low- and middle-income countries: a systematic review and meta-analysis. PLoS Med 11: e1001644.[Crossref] [Google Scholar]
  30. Leclerc HDAA, Mossel DAA, Edberg SC, Struijk CB, , 2001. Advances in the bacteriology of the coliform group: their suitability as markers of microbial water safety. Annu Rev Microbiol 55: 201234.[Crossref] [Google Scholar]
http://instance.metastore.ingenta.com/content/journals/10.4269/ajtmh.16-0322
Loading
/content/journals/10.4269/ajtmh.16-0322
Loading

Data & Media loading...

  • Received : 25 Apr 2016
  • Accepted : 05 Jan 2017

Most Cited This Month

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error