Utility of EC 3M™ Petrifilm™ and sanitary surveys for source water assessment in Nyabushozi County, south-western Uganda

 

 

Amber L Pearson^I; Marilyn C Roberts^II; Olusegun O Soge^II; lana Ivanova^II; Jonathan D Mayer^III; John S Meschke^IV

^IDepartments of Geography and Global Health, University of Washington, Box 353550, Seattle, WA 98195, USA
^IIDepartments of Pathobiology and Environmental and Occupational Health Sciences, University of Washington, Box 357234, Seattle, WA 98195
^IIIDepartments of Geography and Epidemiology, University of Washington, Box 353550, Seattle, WA 98195, USA
^IVDepartment of Environmental and Occupational Health Sciences, University of Washington, Box 354695, Seattle, WA 98195

Correspondence

 

 

---

ABSTRACT

The majority of people in developing nations rely on untreated or minimally treated surface and shallow groundwater sources which are prone to faecal contamination. This study evaluated the utility of EC 3M™ Petrifilm™ and sanitary inspection forms (SIFs) as tools to assess 47 water sources and identify hazards of contamination in two rural Ugandan villages (90% were surface sources). Water samples were cultured on EC 3M™ Petrifilm™, which are intended for the enumeration of E. coli and total coliforms following 24 h incubation at 37°C. Isolated bacteria were cultured on MacConkey agar and identified using standard biochemical tests, while selected isolates were verified by sequencing 16S rRNA genes. From 105 Petrifilms, 110 presumptive E. coli were isolated and identified to genus level. However, only 33 presumptive E. coli isolates from 14 water sources (representing 27 distinct strains as determined by PFGE) were confirmed E. coli. The other presumptive E. coli isolates were identified as Citrobacter, Enterobacter, Proteus, Salmonella and Yersinia species. SIFs used an adapted survey designed for urban water sources of Uganda. The form yielded an SIF score based on binary data and characterized potential sources of contamination. SIF scores alone offered little information to distinguish between contamination levels of surface water sources, but the information collected in the surveys could be used to identify ways to improve sources. The results of this study suggest that the use of sanitary surveys may assist in identifying potential pollution sources that may be targeted to protect water sources. Bacterial monitoring using EC 3M™ Petrifilms™ may be effective for the screening of relative levels of contamination of source waters, including surface sources.

Keywords: drinking water, developing countries, sanitary survey, EC 3M™ Petrifilm™

---

 

"Full text available in PDF"

 

References

BELOTI V, DE SOUZA JA, BARROS MAF, NERO LA, DE MATTOS MR, GUSMAO VV and DE MORALES LB (2003) Evaluation of petrifilm™ EC and HS for total coliforms and Escherichia coli enumeration in water. Braz. J. Microbiol. 34 301-304.         [ Links ]

BAUMGARTNER A, GRAND M, SIMMEN A and HALVAX M (1993) Quantitative analysis of Escherichia coli in water: comparison of ECD-agar and petrifilm™. Mitt.Geb. Lebensmittelunters. Hyg. 83 (3) 382-387.         [ Links ]

BYAMUKAMA D, MACH R, KANSIIME F, MANAFI M and FARNLEITNER AH (2005) Discrimination efficacy of fecal pollution detection in different aquatic habitats of a high-altitude tropical country, using presumptive coliforms, Escherichia coli, and Clostridium perfringens spores. Appl. Environ. Microbiol. 71 (1) 65-71.         [ Links ]

BYAPPANAHALLI M and FUJIOKA R (2004) Indigenous soil bacteria and low moisture allow fecal bacteria to multiply and become a minor population in tropical soils. Water Sci. Technol. 50 (1) 27-32.         [ Links ]

FUNKE G (2003) In: Murray PR, Baron EJ, Jorgensen JH, Pfaller MA and Yolken RH (eds.) Manual of Clinical Microbiology (8^th edn.). ASM Press, Washington, D.C. 334-344.         [ Links ]

GRABOW WOK (1996) Waterborne diseases: Update on water quality assessment and control. Water SA 22 (2) 193-202.         [ Links ]

GREISEN K, LOEFFELHOLZ M, PUROHIT A and LENONG D (1994) Probes for the 16S rRNA gene of most species of pathogenic bacteria, including bacteria found in cerebrospinal fluid. J. Clin. Microbiol. 32 335-351.         [ Links ]

HÖRMAN A and HÄNNINEN ML (2006) Evaluation of the lactose Tergitol-7, m-Endo LES, Colilert 18, Readycult Coliforms 100,Water-Check-100, 3M petrifilm EC and DryCult Coliform test methods for detection of total coliforms and Escherichia coli in water samples. Water Res. 40 3249-3256.         [ Links ]

HOWARD G, PEDLEY S, BARRETT M, NALUBEGA M and JOHAL K (2003) Risk factors contributing to microbiological contamination of shallow groundwater in Kampala, Uganda. Water Res. 37 (14) 3421-3429.         [ Links ]

JANKE R, MOSCOU R and POWELL M (2006) PK-13 W-6 Total Coliform and E. coli: Bacteria Citizen Science. Water Quality Testing Series, Kansas State University, Manhattan, Kansas, USA.         [ Links ]

LECLERC H, MOSSEL DAA, EDBERG SC and STRUIJK CB (2001) Advances in the bacteriology of the coliform group: Their suitability as markers of microbial water safety. Annu. Rev. Microbiol. 55 201-34.         [ Links ]

LLOYD B and J BARTRAM (1991) Surveillance solutions to microbiological problems in water quality control in developing countries. Water Sci. Technol. 24 (2) 61-75.         [ Links ]

McCarthy ts, gumbricht t, stewart rg, brandt d, HANCOX PJ, MCCARTHY J and DUSE AG (2004) Wastewater disposal at safari lodges in the Okavango Delta, Botswana. Water SA 30 (1) 121-128.         [ Links ]

MEDEMA GJ, SHAW S, WAITE M, SNOZZI M, MORREAU A and GRABOW W (2003) Catchment characterization and source water quality. In: A Dufour, M Snozzi, W Koster, J Bartram, E Ronchi and L Fewtrell (eds.) Assessing Microbial Safety of Drinking Water: Improving Approaches and Methods. IWA Publishing, London, UK.         [ Links ]

NIWAGABA C, S GODFREY, A GISAGARA and G HOWARD (2003) System assessment to develop water safety plans. Proc. WEDC Int. Conf. September 22-26, 2003. Abuja, Nigeria.         [ Links ]

PEDLEY S and G HOWARD (1997) The public health implication of groundwater microbiology. Q. J. Eng. Geol. 30 (2) 179-188.         [ Links ]

SMITH M and HUSARY S (2000) Sanitary investigations as a sanitation monitoring tool. Proc. WEDC Conf.: Water, Sanitation and Hygiene: Challenges of the Millennium. 5-9 November, 2000. Dhaka, Bangladesh.         [ Links ]

SCHRAFT H and WATTERWORTH LA (2005) Enumeration of heterotrophs, fecal coliforms and Escherichia coli in water: comparison of 3M petrifilm plates with standard plating procedures. J. Microb. Methods 60 335-342.         [ Links ]

VAIL JH, MORGAN R, MERINO CR, GONZALES F, MILLER R and RAM JL (2003) Enumeration of waterborne Escherichia coli with petrifilm plates: comparison to standard methods. J. Environ. Qual. 32 368-373.         [ Links ]

VERDU ME, COLL P, FONTANALS D, MARCH F, PONS I, SANFELIU I and PRATS G (1996) Endemic meningococcal disease in Cerdanyola, Spain, 1987-93: Molecular epidemiology of the isolates of Neisseria meningitidis. Clin. Microb. Infect. 2 168-178.         [ Links ]

WOHLSEN T, BATES J, VESEY G, ROBINSON WA and KATOULI M (2006) Evaluation of the methods for enumerating coliform bacteria from water samples using precise reference standards. Lett. Appl. Microb. 42 350-356.         [ Links ]

WORLD HEALTH ORGANIZATION (WHO) (1993) WHO Guidelines for Drinking Water Quality. Vol. 2 (1) WHO, Geneva, Switzerland.         [ Links ]

WORLD HEALTH ORGANIZATION (WHO) (2000) Monitoring and assessment of microbiologic quality. Proc. Drinking Water Seminar. WHO, Geneva, Switzerland, Downloaded from http://www.who.int/water_sanitation_health/dwq/S02.pdf on 22January 2008.         [ Links ]

WORLD HEALTH ORGANIZATION (WHO) (2002) The World Health Report 2002: Reducing Risks, Promoting Healthy Life. WHO, Geneva, Switzerland. WORLD HEALTH ORGANIZATION (2006) Guidelines for Drinking-Water Quality. Vol. 1. WHO, Geneva, Switzerland.         [ Links ]

XIA M, WHITTINGTON WL, HOLMES KK, PLUMMER F and ROBERTS MC (1995) Pulsed-field gel electrophoresis for genomic analyses of Neisseria gonorrhoeae. J. Infect. Dis. 171 455-458.         [ Links ]

3M (2001) Petrifilm E. coli / Coliform Count Plate Interpretation Guide. 3M. St. Paul.         [ Links ]

 

 

Correspondence:
206-221-5470
Fax: 206-543-8123
E-mail: jmeschke@u.washmgton.edu

Received 15 November 2007
Accepted in revised form 15 February 2008