Also known as: Cyanobacterium-like, coccidia-like, and Cyclospora-like bodies (CLBs) Cyclospora infection = cyclosporiasis
Hospital: Report by IDSS, facsimile, mail or phone
Lab: Report by IDSS, facsimile, mail or phone
Physician: Report by facsimile, mail or phone
Local Public Health Agency (LPHA): Follow-up required.
Iowa Department of Public Health
Disease Reporting Hotline: (800) 362-2736
Secure Fax (515) 281-5698
This disease is caused by Cyclospora cayetanensis, a single cell microscopic protozoan parasite. Humans with cyclosporiasis shed the parasite in a non-infectious form that takes from several days to a couple of weeks to mature into its infectious form. The time required for maturation to the infectious form depends on factors such as temperature and moisture.
B. Clinical Description
This parasite infects the small intestine (bowel) and typically causes watery diarrhea, which can be severe. Other symptoms can include nausea, vomiting, abdominal cramping, gas and bloating, fatigue and loss of appetite, anorexia, weight loss, abdominal pain, myalgias, and low-grade fever. Occasionally, infected individuals may not have any symptoms. Untreated, symptoms may last from several days to several weeks (longer in immunocompromised individuals), and weight loss can be significant (exceeding 20 pounds in some cases).
Humans are the only known reservoir for Cyclospora cayetanensis, however animal reservoirs have been suspected. Cyclospora has been found on a variety of fruits and vegetables including lettuce and raspberries.
D. Modes of Transmission
Current knowledge of human cyclosporiasis suggests that it is not likely to be transmitted directly from person-to-person. After being shed in human stool, the parasite must undergo developmental changes (taking days to weeks) before becoming infectious. Humans become infected by consuming food or water that has been contaminated with human feces containing Cyclospora.
E. Incubation Period
The incubation period is about 1 - 2 weeks, with an average of 1 week.
F. Period of Communicability or Infectious Period
People may shed Cyclospora parasites for days to over one month (while actively ill). It is not known how long the parasite may be shed after symptoms have stopped.
Cyclosporiasis was first recognized in 1979. The parasite appears to be widely distributed throughout the world with a predominant number of cases occurring during the warmer months. Cyclospora may be transmitted by ingestion of water or food contaminated with oocysts. Outbreaks linked to contaminated water and fresh produce have been reported in recent years. Large outbreaks of cyclosporiasis in the United States occurred during the summers of 1996 and 1997; a majority of those cases had consumed imported raspberries. Iowa experienced an outbreak of 148 cases in 2013 linked to imported salad greens.
To date, the fresh produce items that have been implicated in U.S. outbreaks include fresh imported raspberries, basil, snow peas, and varieties of lettuce. Persons of all ages are at risk for infection. Persons living or traveling in developing countries may be at increased risk.
H. Bioterrorism Potential
I. Additional Information
The Council of State and Territorial Epidemiologists (CSTE) surveillance case definitions for Cyclospora can be found at: wwwn.cdc.gov/NNDSS/script/casedefDefault.aspx
CSTE case definitions should not affect the investigation or reporting of a case that fulfills the criteria in this chapter. (CSTE case definitions are used by the state health department and the CDC to maintain uniform standards for national reporting.)
American Academy of Pediatrics. 2003 Red Book: Report of the Committee on Infectious Diseases, 26th Edition. Illinois, Academy of Pediatrics, 2003.
CDC Website. Cyclospora Infection. www.cdc.gov/parasites/cyclosporiasis/epi.html
Heymann, D., ed., Control of Communicable Diseases Manual, 20th Edition. Washington, DC, American Public Health Association, 2015.
Soave, Rosemary. Cyclospora: An Overview. Clinical Infectious Diseases, 1996; 23:429-3