Submitted to: Journal of American Society for Tropical Medicine and Hygiene
Publication Type: Abstract Only
Publication Acceptance Date: November 1, 1999
Publication Date: November 1, 1999
Infection with the emerging protozoal pathogen, Cyclospora cayetanensis, has been linked to the consumption of fruits and vegetables. Obtaining appreciable numbers of oocysts from these foodstuffs has been difficult, however. One source of oocysts for experimental purposes is Indonesia, where US military personnel can acquire acute or chronic diarrheal disease, ,in which Cyclospora and Cryptosporidium oocysts are observed in the feces. We isolated oocysts from fecal specimens, obtained from these non-indigenous patients during their visits to clinics in Jakarta, and extracted DNA for use in PCR assays. Using the Relman et al. 18S rRNA nested PCr, we amplified nested product (294 bp) from 3 of 6 specimens. Sequencing of these products indicated >99% homologies with the published sequence of C. cayetanensis. More recently, we have had some success in amplifying a larger (1 kb) 18S rRNA fragment from another fecal specimen by ymodifying the PCR parameters. The results on ongoing efforts to characterize these isolates at the molecular level will be presented. Some Cyclospora patients had additional oocyst-like objects present in their feces, with light microscopy morphology similar to Cryptosporidium. We will present data on our attempts to characterize these Cryptosporidium isolates as well. Our results to date indicate that expatriates are important sources of C. cayetanensis oocysts that can be used for research efforts conduted in the United States.