Volume 76, Issue 5
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


is a significant cause of diarrheal illness worldwide, especially among children and immunocompromised patients. Currently used diagnostic techniques are time-consuming, require skilled technicians, and are not useful for quantification of oocysts in fecal and environmental samples. In this study, we examined the use of a real-time polymerase chain reaction (PCR) assay for detecting and quantifying in three distinct and progressively more complex matrices: phosphate-buffered saline (PBS), HCT-8 cells (human ileocecal carcinoma), and human fecal specimens. A reliable standard curve was generated using the PBS samples spiked with pure oocysts, and oocyst starting quantities were calculated for the infected HCT-8 cell and spiked fecal samples. The assay detected in samples infected/spiked with ≥10 oocysts/sample and detected both and in clinical specimens. This assay is useful in a variety of samples in the research laboratory and will likely prove to be a useful tool in the clinical laboratory.


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  • Received : 28 Aug 2006
  • Accepted : 13 Feb 2007

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