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What is cryptosporidiosis?

Cryptosporidiosis (KRIP-toe-spo-rid-ee-OH-sis) or Crypto is a diarrheal disease caused by a microscopic parasite called Cryptosporidium. The parasite lives in the intestine of infected humans and animals.

Chlorination and other methods of water purification will not kill Cryptosporidium, making it one of the most common causes of waterborne disease (recreational and drinking water) in the U.S. Crypto has also been responsible for outbreaks in child care settings, foodborne illness outbreaks associated with contaminated foods or ill food handlers, and through contact with livestock or animals at petting zoos. Between 2001 and 2008 in California there were over 2,000 reported cases of Crypto.

How is cryptosporidiosis spread?

Crypto is a contagious disease. When a person or animal infected with Crypto begins to have symptoms, millions of Crypto parasites are shed in their feces during a bowel movement. The shedding of the parasites can last for weeks after the symptoms stop.

Crypto may be found in soil, food, water, or surfaces that have been contaminated with the feces from infected humans or animals. You may become infected even if you can’t see the contamination

How can you get Crypto?

You can get Crypto if you:

  • Drink water contaminated with Crypto parasites.
  • Swim in water contaminated with Crypto parasites & accidentally swallow some of it.
  • Eat food contaminated with Crypto.
  • Touch your hand to your mouth if your hand has been in contact with a contaminated surface or
  • Have close contact with other infected people or animals — especially their feces — which can
    allow the parasite to be transmitted from your hands to your mouth.
  • Are exposed to feces from an infected person during sexual activity.

What are the symptoms of cryptosporidiosis?

Symptoms of Crypto infection can begin two to ten days after becoming infected with the parasite.
Watery diarrhea is the most common symptom. Other symptoms include: stomach cramps or pain, dehydration, nausea, vomiting, fever, and weight loss.

In persons with healthy immune systems, symptoms usually last about one to two weeks. Some people
with Crypto will have no symptoms at all. People with weakened immune systems, including
those with HIV/ AIDS and transplant recipients, may be very ill for a much longer period of time
and can have serious complications. More information regarding diagnosis and treatment for people with weakened immune systems can be found on the U.S. Centers for Disease Control and Prevention crypto webpage.

How is cryptosporidiosis diagnosed?

Crypto can be difficult to diagnose. Routine tests for diarrheal illnesses do not detect Crypto. If you feel that you have Crypto, tell your health care provider. Your health care provider can request specific testing for the parasite. Because testing for Crypto can be difficult, you may be asked to submit fecal specimens over several days.

How is cryptosporidiosis treated?

It is very important to see your health care provider if you think you may have Crypto.
Most people who have healthy immune systems will recover without treatment. Prescription medicine
is available if needed.

How can cryptosporidiosis be prevented?

  • Wash hands with soap and water for at least 20 seconds, rubbing hands together vigorously and
    scrubbing all surfaces:
    • Before preparing or eating food
    • After using the toilet
    • After changing diapers or cleaning up a child who has used the toilet
    • Before and after tending to someone who is ill with diarrhea
    • After handling an animal or animal waste 
  • Purify untreated water (such as from a stream or a lake) before drinking by:
    • Boiling water for at least one minute. Above 6500 feet, boil water for at least three minutes.
    • Using special water filters that can remove Crypto.
  • Around animals:
    • Minimize contact with the feces of all animals, particularly young animals.
    • When cleaning up animal feces, wear disposable gloves, and always wash hands when finished.
    • Wash hands after any contact with animals or their living areas.
  • If you have a weakened immune system, speak to your health care provider. Additional precautions
    may be recommended.

How do I protect others if I have diarrhea or cryptosporidiosis?

  • Children with diarrhea or Crypto
    • Children with diarrhea should be excluded from child care settings until the diarrhea has stopped.
  • At recreational water venues (pools, water slides, interactive fountains, lakes, ocean)
    • Do not swim or participate in water activities if you have diarrhea (this is essential for
      children in diapers). If you have been diagnosed with cryptosporidiosis, do not swim for at least 2 weeks after diarrhea stops.
    • Shower before entering the water.
    • Wash children thoroughly (especially their bottoms) with soap and water after they use the toilet or their diapers are changed and before they enter the water.
    • Take children on frequent bathroom breaks and check their diapers often.
    • Change diapers in the bathroom, not at the poolside.

What is public health doing about cryptosporidiosis?

The California Department of Public Health (CDPH) and local health departments (LHDs) monitor
cryptosporidiosis in California. If an outbreak of Crypto is reported, CDPH and LHDs public health
will investigate to find the cause, fix the problem, and educate the public.

To help prevent spread of cryptosporidiosis to others, LHDs may restrict persons with
cryptosporidiosis from certain types of work (such as food handling) or other activities until the
person has not had diarrhea for 48 hours. Persons with Crypto should stay out of public pools for
at least 2 weeks after diarrhea has stopped.

What is public health doing to ensure that my drinking water is not contaminated with Cryptosporidium?

Public water systems must follow rules and standards set by the U.S. Environmental Protection
Agency. These requirements reduce the levels of Cryptosporidium in public drinking water so that
the risk of contamination is very low.

Private wells and individual water systems may not have the same level of monitoring as large
public water systems. Owners of these systems are responsible for ensuring that their well water is
safe from contaminants, including Cryptosporidium.

Where can I get more information on cryptosporidiosis?

You can get more information from: 

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