How does Cyclospora cayetanensis spread?
The full host range of C. cayetanensis is currently unknown. At this time, humans are the only known host, with chimpanzees and other primates thought to be potential reservoirs. Infection with C. cayetanensis begins when ingested particles invade the epithelial cells of the small intestine. C. cayetanensis will then replicate and continue to spread to nearby cells. It is this self-limiting (short-lived) stage that causes most of the symptoms associated with this parasite. During infection, some of the parasitic cells undergo a sexual reproductive stage, where survival structures, called “oocysts,” are produced. These are the structures that eventually pass in the host’s fecal matter and spread infection. After about one to two weeks, shed oocysts become “activated” (i.e., infectious), and if consumed through contaminated food or water, the disease will spread to the new host. Due to this lag time in infectivity, direct person-to-person contamination is unlikely. The full disease cycle
