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Cryptosporidium species is an important enteric parasitic pathogen in the United States (US), causing an estimated 300,000 infections per year. Leading sources of Cryptosporidium infection include direct contact with an infected person or animal, ingestion of water or food contaminated by human or animal feces, and travel to highly-endemic areas.

Cryptosporidium is resistant to current methods of water purification. In the US, it is the most frequently recognized cause of reported recreational water associated outbreaks, particularly in disinfected venues, and is a recognized cause of drinking water associated outbreaks. Outbreaks in child care settings are also commonly reported.

Acute illness, usually gastroenteritis including watery diarrhea, occurs after an incubation period of 1 to 12 days. Symptoms in immunocompetent persons usually last 1 to 2 weeks. Infected persons who are immunodeficient, including those with HIV, may develop chronic, fulminant disease. Chronic intestinal cryptosporidiosis is an AIDS defining condition. Asymptomatic infections in people and animals are a frequent source of Cryptosporidium transmission.

Preventing Cryptosporidiosis

Washing hands is the most effective means of preventing cryptosporidiosis. To avoid becoming infected, follow these precautions:

  • Practice good hygiene (hand washing).
  • Avoid water that might be contaminated.
  • If you are unable to avoid using or drinking water that might be contaminated, then you can make the water safe to drink by boiling it or filtering it.
  • Avoid food that might be contaminated.
  • Take extra care when traveling.
  • Avoid fecal exposure during sexual activity.
  • For people with weakened immune systems, sex, including oral sex, that involves possible contact with stool should be avoided. Immunocompromised individuals should also avoid the stool of all animals and wash their hands thoroughly after any contact with animals or the living areas of animals. Immunocompromised persons may also wish to wash, peel, or cook all vegetables and to take extra measures, such as boiling or filtering their drinking water, to ensure its safety.

    Last modified on: 8/9/2016 11:54 AM