Cryptosporidium Oocyst Detection in Water Samples: Floatation Technique Enhanced with Immunofluorescence Is as Effective as Immunomagnetic Separation Method
2
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
Cryptosporidium can cause gastrointestinal diseases worldwide, consequently posing public health problems and economic burden. Effective techniques for detecting contaminated oocysts in water are important to prevent and control the contamination. Immunomagnetic separation (IMS) method has been widely employed recently due to its efficiency, but, it is costly. Sucrose floatation technique is generally used for separating organisms by using their different specific gravity. It is effective and cheap but time consuming as well as requiring highly skilled personnel. Water turbidity and parasite load in water sample are additional factors affecting to the recovery rate of those 2 methods. We compared the efficiency of IMS and sucrose floatation methods to recover the spiked Cryptosporidium oocysts in various turbidity water samples. Cryptosporidium oocysts concentration at 1, 101, 102, and 103 per 10 ㎕ were spiked into 3 sets of 10 ml-water turbidity (5, 50, and 500 NTU). The recovery rate of the 2 methods was not different. Oocyst load at the concentration < 102 per 10 ml yielded unreliable results. Water turbidity at 500 NTU decreased the recovery rate of both techniques. The combination of sucrose floatation and immunofluorescense assay techniques (SF-FA) showed higher recovery rate than IMS and immunofluorescense assay (IMS-FA). We used this SF-FA to detect Cryptosporidium and Giardia from the river water samples and found 9 and 19 out of 30 (30% and 63.3%) positive, respectively. Our results favored sucrose floatation technique enhanced with immunofluorescense assay for detecting contaminated protozoa in water samples in general laboratories and in the real practical setting.
Abstract
Cryptosporidium can cause gastrointestinal diseases worldwide, consequently posing public health problems and economic burden. Effective techniques for detecting contaminated oocysts in water are important to prevent and control the contamination. Immunomagnetic separation (IMS) method has been widely employed recently due to its efficiency, but, it is costly. Sucrose floatation technique is generally used for separating organisms by using their different specific gravity. It is effective and cheap but time consuming as well as requiring highly skilled personnel. Water turbidity and parasite load in water sample are additional factors affecting to the recovery rate of those 2 methods. We compared the efficiency of IMS and sucrose floatation methods to recover the spiked Cryptosporidium oocysts in various turbidity water samples. Cryptosporidium oocysts concentration at 1, 101, 102, and 103 per 10 ㎕ were spiked into 3 sets of 10 ml-water turbidity (5, 50, and 500 NTU). The recovery rate of the 2 methods was not different. Oocyst load at the concentration < 102 per 10 ml yielded unreliable results. Water turbidity at 500 NTU decreased the recovery rate of both techniques. The combination of sucrose floatation and immunofluorescense assay techniques (SF-FA) showed higher recovery rate than IMS and immunofluorescense assay (IMS-FA). We used this SF-FA to detect Cryptosporidium and Giardia from the river water samples and found 9 and 19 out of 30 (30% and 63.3%) positive, respectively. Our results favored sucrose floatation technique enhanced with immunofluorescense assay for detecting contaminated protozoa in water samples in general laboratories and in the real practical setting.
참고문헌 (18)
- Feng YY, "Effect of particles on the recovery of Cryptosporidium oocysts from source water samples of various turbidities", Appl Environ Microbiol, 69, pp.1898~1903 (2003)
- Kuczynska E, "Comparison of immunofluorescence assay and immunomagnetic electrochemiluminescence in detection of Cryptosporidium parvum oocysts in karst water samples", J Microbiol Methods, 53, pp.17~26 (2003)
- Fujino T, "Detection of a small number of Cryptosporidium parvum oocysts by sugar floatation and sugar centrifugation methods", J Vet Med Sci, 68, pp.1191~1193 (2006)
- LeChevallier MW, "Comparison of method 1623 and cell culture-PCR for detection of Cryptosporidium spp. in source waters", Appl Environ Microbiol, 69, pp.971~979 (2003)
- Miller WA, "Farm factors associated with reducing Cryptosporidium loading in storm runoff from dairies", J Environ Qual, 37, pp.1875~1882 (2008)
- Downey AS, "Maximizing recovery and detection of Cryptosporidium parvum oocysts from spiked eastern oyster (Crassostrea virginica) tissue samples", Appl Environ Microbiol, 73, pp.6910~6915 (2007)
- Sacco C, "Removal of Cryptosporidium and Giardia in drinking water treatment in a Tuscan area", Ann Ig, 18, pp.117~126 (2006)
- Iacovski RB, "Detection and enumeration of Cryptosporidium sp. oocysts in sewage sludge samples from the city of Florianopolis (Brazil) by using immunomagnetic separation combined with indirect immunofluorescence assay", Waste Manag Res, 22, pp.171~176 (2004)
- Chesnot T, "Quantitative and qualitative comparison of density-based purification methods for detection of Cryptosporidium oocysts in turbid environmental matrices", J Microbiol Methods, 58, pp.375~386 (2004)
- Ware MW, "Evaluation of an alternative IMS dissociation procedure for use with Method 1622: Detection of Cryptosporidium in water", J Microbiol Methods, 55, pp.575~583 (2003)
- Bonadonna L, "Occurrence of Cryptosporidium oocysts in sewage effluents and correlation with microbial, chemical and physical water variables", Environ Monit Assess, 75, pp.241~252 (2002)
- Campbell A, "Immunomagnetic separation of Cryptosporidium oocysts from water samples: Round robin comparison of techniques", Water Sci Technol, 35, pp.397~401 (1997)
- McNabb SJ, "Comparison of sedimentation and floatation techniques for identification of Cryptosporidium sp. oocysts in a large outbreak of human diarrhea", J Clin Microbiol, 22, pp.587~589 (1985)
- Muchiri JM, "Seasonality of Cryptosporidium oocyst detection in surface waters of Meru, Kenya as determined by two isolation methods followed by PCR", J Water Health, 7, pp.67~75 (2009)
- Kuhn RC, "Effect of pH and magnetic material on immunomagnetic separation of Cryptosporidium oocysts from concentrated water samples", Appl Environ Microbiol, 68, pp.2066~2070 (2002)
- Yakub GP, "Evaluation of immunomagnetic separation for recovery of Cryptosporidium parvum and Giardia duodinalis from high-iron matrices", Appl Environ Microbiol, 66, pp.3628~3631 (2000)
- Rodgers MR, "Identification of algae which interfere with the detection of Giardia cysts and Cryptosporidium oocysts and a method for alleviating this interference", Appl Environ Microbiol, 61, pp.3759~3763 (1995)
- Sutthikornchai C, "Protozoal contamination of water used in Thai frozen food industry", Southeast Asian J Trop Med Public Health, 36, pp.41~45 (2005)