Encyclopedia of Parasitology

Living Edition
| Editors: Heinz Mehlhorn

Cyclospora cayetanensis

  • Heinz MehlhornEmail author
Living reference work entry
DOI: https://doi.org/10.1007/978-3-642-27769-6_4235-1


Human Feces Caribbean Island Prepatent Period Affected Person Sporulated Oocyst 
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Greek: kyclos = spherical, round; sporos = spore, capsule, semen; cayetanensis = Caribbean origin.

Geographic Distribution/Epidemiology

Worldwide (in warmer countries) several 100,000 persons are infected. Probably all had been infected abroad from their homes during holidays. The species name was given since the first description was done based on material of a patient who came from a Caribbean island.

Morphology/Life Cycle

Starting from 1985 spherical cystic stages of 8–10 μm in diameter had been observed in increasing numbers in the feces of immunocompromised and immunocompetent persons. These stages were at first kept for cyanobacteria and thus described as CLB bodies (= cyanobacteria-like bodies). Other investigators identified these small globules as peculiar stages of the genus Cryptosporidium , because similar ones were discovered at the same time in large numbers in the feces of AIDS patients. Intense experiments to sporulate these stages (Lit. see (Ortega et al. 1998)) showed later that these parasites are typical coccidians (Sporozoa, Apicomplexa, Alveolata). The CLB bodies thus represent nothing else than the oocysts of a coccidian species, which is now called Cyclospora cayetanensis. Related species have been described in the intestines of insectivores, rodents, reptiles, and millipedes, too (e.g., C. caryolytica in moles and C. viperae in snakes). When excreted in the feces the oocysts of C. cayetanensis sporulate outside of the human body within 5–13 days at 25–32 °C, thus forming inside of the oocysts wall two ovoid sporocysts with two bended sporozoites which reach a size of 9 × 1.5 μm (Fig. 1). Similar oocysts have also been found in feces of chimpanzees and other monkeys; however, it is still today unclear whether they are related to those found in human feces. In any way they were described as C. cercopitheci, C. colobi, and C. papionis.
Fig. 1

Diagrammatic representations of an unsporulated and a sporulated oocyst of Cyclospora cayetanensis. The unsporulated form had originally been described as cyanobacteria-like body (CLB)

Symptoms of Disease

Immunocompromised and immunocompetent persons show identical symptoms of disease, since both groups suffer for 2–9 weeks from diarrheas that appear watery and are produced three to four times per day. These diarrheas may disappear also without treatment, but affected persons are hit by weakness and abdominal pain.


Microscopic investigation of native fluid feces or concentration methods (S.A.F.C., M.I.F.C.) show the typical oocysts. The Ziehl-Neelsen stain also can be used to show the oocyst walls (Figs. 1 and 2).
Fig. 2

Light micrograph of an sporulated oocyst of C. cayetanensis


Oral uptake of sporulated oocysts within fecally contaminated food or within drinking water.


Avoid potentially contaminated food or drinking water.

Incubation Period

Two to seven days.

Prepatent Period

About 1 week.


Immunocompetent persons: 2 weeks; immunocompromised persons: up to 7–12 weeks.


Not necessary in persons with light symptoms. In cases of severe diarrheas cotrimoxazole (2 × 800 mg sulfamethoxazole/160 mg trimethoprim daily for a week) showed clearance of symptoms. Diarrheas of children were stopped within 4 days by application of 5 or 25 mg cotrimoxazole per kg body weight for 3 days.


  1. Ortega YR et al (1998) Cyclospora cayetanensis. Adv Parasitol 40:339–418CrossRefGoogle Scholar

Further Readings

  1. Chacin-Bonilla L (2010) Epidemiology of Cyclospora cayetanensis: a review focused in endemic areas. Acta Trop 115:181–193CrossRefPubMedGoogle Scholar
  2. Legua P, Seas C (2013) Cystoisospora and Cyclospora. Infect Dis 26:479–483Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.Institut für ZoomorphologieZellbiologie und Parasitologie Universitätsstraße 1DüsseldorfGermany