Purpose of review: Infection with Cyclospora cayetanensis continues to pose many questions, both in endemic populations and in travelers and food-borne outbreaks. The present review discusses existing knowledge but focuses more on what is yet to be learned about this infection.
Recent findings: Information on the parasite in endemic settings continues to be gathered, and similarities to and differences from other intestinal coccidia, especially Cryptosporidium spp., are becoming clearer. Food-borne outbreaks in North America continue despite efforts to identify and limit importation of particular items, such as berries, at certain times of the year. Study of Cyclospora spp. found in east African primates has shed some light on human infection but raises many new questions regarding the biology of the organism.
Summary: Despite new information being gathered regarding Cyclospora spp., including infection rates in various age and population groups, significant gaps remain in our knowledge of such basic issues as the factors that influence infectivity, seasonality, mode of food contamination, and geographic distribution. These gaps highlight the need for continued study on a variety of fronts, including surveillance, and clinical and basic biology.