A Cryptosporidium is a protozoan microbe associated with the disease cryptosporidiosis in man. The disease can be transmitted through ingestion of drinking water, person-to-person contact,

or other pathways, and can cause acute diarrhea, abdominal pain, vomiting, fever, and can be fatal.

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A cryptosporidium is a protozoan (single-celled organism) that can infect humans, usually as a result of exposure to contaminated drinking water.

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A Cryptosporidium is a microorganism commonly found in lakes and rivers which is highly resistant to disinfection. Cryptosporidium has caused several large outbreaks of gastrointestinal illness, with symptoms that include diarrhea, nausea, and/or stomach cramps. People with severely weakened immune systems are likely to have more severe and more persistent symptoms than healthy individuals.