Cryptosporidium

apicomplexan genus

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June 25, 2026

Quick Summary

Cryptosporidium is a genus of protozoans that are parasitic in the gut of vertebrates, including humans. These organisms can sometimes cause diarrhea. The infection or disease caused by Cryptosporidium is known as cryptosporidiosis.12

Cryptosporidium belongs to the phylum Apicomplexa, which are typically spore-producing protozoans. All apicomplexans are parasitic and live within the body cavities or cells of animals. Some genera within this phylum are pathogenic, such as Plasmodium, which causes malaria. Apicomplexans absorb nutrients from their host and reproduce through asexual or sexual reproduction.3

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protozoan
Protozoans and disease
The apicomplexan Cryptosporidium is a protozoan parasite of humans and other mammals that was discovered in the 1970s. It has a one-host life cycle and lives inside the cells lining the intestines and sometimes the lungs. Cryptosporidium carries out all the asexual reproductive stages typical of an…
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The apicomplexan Cryptosporidium is a protozoan parasite of humans and other mammals that was discovered in the 1970s. It has a one-host life cycle and lives inside the cells lining the intestines and sometimes the lungs. Cryptosporidium carries out all the asexual reproductive stages typical of an…
Read More