Evaluation of the immunofluorescence procedure for detection of Giardia cysts and Cryptosporidium oocysts in water.
AUTOR(ES)
LeChevallier, M W
RESUMO
The accurate determination of the presence of Giardia cysts and Cryptosporidium oocysts in surface waters requires a reliable method for the detection and enumeration of these pathogenic organisms. Published methods have usually reported recovery efficiencies of less than 50% for both cysts and oocysts. Typically, the losses are greater for Cryptosporidium oocysts than they are for Giardia cysts. The purpose of this study was to examine procedures used for sample collection, elution, concentration, and clarification to determine when losses of cysts and oocysts occurred during processing. The results showed that major losses of cysts and oocysts occurred during centrifugation and clarification. Depending on the centrifugation force, oocyst losses of as high as 30% occurred for each centrifugation step. A 1.15-specific-gravity Percoll-sucrose gradient was needed to optimize recovery of oocysts from natural water samples. Minor improvements in the procedure could be accomplished by selecting a filter other than the recommended 1-micron-pore-size (nominal-porosity) polypropylene filter.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=167330Documentos Relacionados
- An evaluation of methods for the simultaneous detection of Cryptosporidium oocysts and Giardia cysts from water.
- Comparison of two methods for detection of Giardia cysts and Cryptosporidium oocysts in water.
- Evaluation of immunofluorescence techniques for detection of Cryptosporidium oocysts and Giardia cysts from environmental samples.
- Sedimentation of Free and Attached Cryptosporidium Oocysts and Giardia Cysts in Water
- Quantitation of Giardia cysts and Cryptosporidium oocysts in fecal samples by direct immunofluorescence assay.
