Parasites - Cryptosporidium (also known as "Crypto")

3D rendering of Cryptosporidium cysts with the organisms inside

Learn more about Cryptosporidium

US Cryptosporidiosis outbreaks - 2009 to 2017. Outbreaks of diarrhea most commonly linked to pools (35%), cattle (15%) and childcare (13%). Click to read the MMWR report.

New report: U.S. Cryptosporidiosis Outbreaks 2009 - 2017

Cryptosporidium is a microscopic parasite that causes the diarrheal disease cryptosporidiosis. Both the parasite and the disease are commonly known as “Crypto.”

There are many species of Cryptosporidium that infect animals, some of which also infect humans. The parasite is protected by an outer shell that allows it to survive outside the body for long periods of time and makes it very tolerant to chlorine disinfection.

While this parasite can be spread in several different ways, water (drinking water and recreational water) is the most common way to spread the parasite. Cryptosporidium is a leading cause of waterborne disease among humans in the United States.