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Cryptosporidiosis is a reportable disease in Oklahoma.  The disease is caused by a parasite called Cryptosporidium.  Cryptosporidium forms a hardy cyst (called an oocyst, pronounced “Oh-oh cyst”) that remains viable in the environment.  Oocysts are very resistant to chlorine, and when they are present in water, can only be removed through filtration or heat.  Cryptosporidium is spread to humans by eating food, drinking water, or placing objects in their mouth that have been contaminated with feces from an infected person or animal.

The symptoms of cryptosporidiosis are characterized by diarrhea, abdominal cramps, fever, loss of appetite, nausea, and vomiting.  Symptoms may come and go, but generally do not recur more than 30 days after the last bout of illness. In immunodeficient persons (such as those with HIV infection, undergoing cancer treatment, or organ recipients) cryptosporidiosis can be a severe, life-threatening illness.  People with HIV are especially vulnerable to cryptosporidiosis, and need to take special precautions against infection with the parasite.  Cryptosporidium is spread to humans through contaminated water, food, cattle, and from person to person because of inadequate handwashing.

Symptoms of cryptosporidiosis appear about 7 days after ingestion of oocysts, but may occur as early as one and as long as 12 days later.  Once infected, a person will excrete the parasite throughout the illness and for several weeks after symptoms end.  Many people are infected with cryptosporidiosis without having symptoms, and may pass the parasite in the stool without knowing it.

Cryptosporidiosis is diagnosed by identifying the parasite in stool using special dyes.  This test is called an “ova and parasite” or “O and P” test.  If not suspected, Cryptosporidium is easily overlooked during lab testing, as it is small and resembles the yeast commonly found naturally in human stool specimens.  Culture, used for diagnosing bacterial enteric diseases like salmonellosis, campylobacteriosis, and illness due to enterohemorrhagic Escherichia Coli (EHEC), will not yield Cryptosporidium for identification.

What can be done to prevent cryptosporidiosis?

  • Regular handwashing with soap and water, whether you are ill or well, is the single most important thing you can do to prevent cryptosporidiosis and other diarrheal illnesses.  This includes after changing a diaper, using the toilet, and before and after preparing food.
  • People with diarrhea should not swim.  Protect others by not swimming in pools or other recreational water sources if experiencing diarrhea.  Persons with cryptosporidiosis should wait 2 weeks after diarrhea stops before going back in the water.
  • When swimming, fishing, water-skiing, or participating in another water-related activity, avoid swallowing water.  Do not drink untreated water, such as that from shallow wells, lakes, rivers, ponds, or streams.
  • Avoid using ice or drinking untreated water during international travel to developing countries where the water supply might be unsafe.
  • Avoid food that might be contaminated by washing/peeling all raw fruits and vegetables before eating, wash all food that will be eaten raw with water that is from a safe source, and avoid eating uncooked foods when traveling in developing countries where the water supply might be unsafe.
  • Avoid fecal exposure during sex.
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