How to differentiate cryptosporidium with cycloprora?
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We compared the epidemiologic characteristics of cyclosporiasis and cryptosporidiosis in data from a cohort study of diarrhea in a periurban community near Lima, Peru. Children had an average of 0.20 episodes of cyclosporiasis/year and 0.22 episodes of cryptosporidiosis/year of follow-up. The incidence of cryptosporidiosis peaked at 0.42 for 1-year-old children and declined to 0.06 episodes/child-year for 5- to 9-year-old children. In contrast, the incidence of cyclosporiasis was fairly constant among 1- to 9-year-old children (0.21 to 0.28 episodes/child-year). Likelihood of diarrhea decreased significantly with each episode of cyclosporiasis; for cryptosporidiosis, this trend was not statistically significant. Both infections were more frequent during the warm season (December to May) than the cooler season (June to November). Cryptosporidiosis was more frequent in children from houses without a latrine or toilet. Cyclosporiasis was associated with ownership of domestic animals, especially birds, guinea pigs, and rabbits.
The coccidian protozoal parasites Cyclospora cayetanensis and Cryptosporidium parvum are recognized diarrheal pathogens among children in developing countries (1–4), but longitudinal data, especially for cyclosporiasis, are sparse. Cyclospora cayetanensis is more closely related genetically to Eimeria species than to Cryptosporidium species (5), and the two organisms have biological differences. For example, C. parvum is infectious when excreted and can be transmitted directly from person to person; Cyclospora cayetanensis requires a period of time in the environment to sporulate into the infectious form (3), decreasing the likelihood of direct person-to-person spread. Cryptosporidium parvum infects both humans and a variety of mammals (6), and evidence is mounting that non-parvum zoonotic Cryptosporidium species can also infect immunocompetent humans (7,8). Conversely, natural or experimental infection of animals with Cyclospora cayetanensis has not been convincingly demonstrated (9–11). Thus, cryptosporidiosis is transmitted through a variety of routes, including contaminated water or food, from person to person, or from animal to person. In contrast, the only major known risk factors for cyclosporiasis are consumption of contaminated water or produce (