Cyclospora is a parasite composed of one cell, too small to be seen without a microscope. The organism was previously thought to be a blue-green alga or a large form of Cryptosporidium. Cyclospora cayetanensis is the only species of this organism found in humans.

Cyclosporiasis is an intestinal illness caused by the parasite Cyclospora

What is cyclospora? 

Cyclospora is a parasite composed of one cell, too small to be seen without a microscope. The organism was previously thought to be a blue-green alga or a large form of cryptosporidium. Cyclospora cayetanensis is the only species of this organism found in humans. The first known human cases of illness caused