Cyclospora cayetanensis

MICROBIOLOGY

• C. cayetanensis is an obligate intracellular, coccidian parasite that infects epithelial cells of the small intestine, destroys the intestinal brush border, and alters mucosal architecture.[8]
• Cyclospora are excreted in the stool as spherical oocysts, 8-10 μm in diameter, which may be shed intermittantly and at low levels. Sporulation or maturation of oocysts occurs after excretion and takes 7-12 days at favorable temperature and humidity.[3]
• Transmission occurs by ingestion of fecally contaminated soil, food and water.[5]
• Humans are the only known host and reservoir. Human-to-human transmission is unlikely as excreted oocysts must sporulate before becoming infectious.[10]
• Both sporadic infections and outbreaks occur. Foodborne outbreaks are associated with fruits and vegetables, i.e., raspberries, mixed salad greens, cilantro, and basil.
• Frequency of outbreaks peaks during spring & summer in the US. Multistate US outbreaks occurred each year from 2018-2022.[12][11]
  
  • Recent advancements in molecular detection methods enhance the capacity to investigate outbreaks.[6]