What is Cryptosporidiosis?
Cryptosporidiosis is a parasitic infection caused by the protozoan Cryptosporidium parvum.
Infectious oocysts (the state in the parasite’s life cycle when the organism is surrounded by a protective shell) of C. parvum are small. They can survive for months in soil under cool dark conditions, for up to a year in low-turbidity water, and are more resistant to chemical agents (including chlorine) than the majority of protozoa.
Who gets Cryptosporidiosis?
Anyone can get cryptosporidiosis. Cryptosporidia is one of the most common causes of waterborne illness in the United States and have been associated with illness worldwide.
Groups at increased risk for infection include:
- Animal handlers
- Men who have sex with men
- The immunecompromised
- Close personal contacts of infected individuals
- Daycare workers
- Health care workers
Peak infection rates occur in the young and decrease progressively with age.
How is Cryptosporidiosis transmitted?
Cryptosporidia have been found in many hosts, including:
- Other domestic mammals
In order for infection to occur, the susceptible host must ingest water or other materials contaminated with the Cryptosporidium oocysts.
As such, important routes of transmission include:
What are the symptoms of Cryptosporidiosis?
Common symptoms include:
- Profuse, watery diarrhea
- Low-grade fever
- Abdominal pain
- Weight loss
In most healthy people (including children), the illness is self-limited, lasting from one to 20 days (average 10 days).
However, in immunodeficient patients, especially those with AIDS, chronic infection may cause:
- Severe diarrhea
- Possibly death
Although infection is usually limited to the gastrointestinal tract, disseminated infection has occurred in immunodeficient patients.
How soon after infection do symptoms appear?
Symptoms appear from one to 12 days after exposure (average seven days).
How long can an infected person spread the disease?
Oocysts appear in the stool when symptoms first begin and continue to be excreted for several weeks after symptoms resolve.
What is the treatment for Cryptosporidiosis?
Other than rehydration and correction of electrolyte abnormalities, no effective therapy exists.
Do people with Cryptosporidiosis need to be excluded from work or school?
Any child with diarrhea should be excluded from child care until symptoms have resolved.
Additionally, symptomatic individuals should be excluded from food handling and from direct care of hospitalized and institutionalized patients.
Physicians and caregivers should place an emphasis on the importance of hand washing and personal hygiene.
How is Cryptosporidiosis diagnosed?
Cryptosporidiosis is usually diagnosed by laboratory examination of stool samples. However, the organism can also be identified in intestinal biopsy sections.
Since the infectious oocysts are excreted from the body intermittently, at least two stool samples should be examined before the test can be considered negative.
How do I avoid getting Cryptosporidiosis?
- Always wash hands thoroughly with warm, soapy water before and after changing diapers, handling food, using the toilet and after playing with pets.
- Do not drink water directly from lakes, rivers, or other untreated sources.
- During a waterborne outbreak in which a “Boil Water Advisory” is issued, boiling water for at least three minutes will eliminate the risk of acquiring cryptosporidiosis.
Should HIV infected and immunodeficient people take special precautions to prevent infection?
The risk for acquiring this infection during a non-outbreak setting is uncertain and current data are inadequate to make recommendations regarding drinking tap water under normal conditions.
Severity of illness is correlated with the level of an individual’s immunosuppression. However, immunodeficient people may wish to consider independent actions that may reduce the risk of waterborne cryptosporidiosis:
- For all water consumption purposes, boil water at least three minutes before using (for elevations above 8,500 feet, boil for five minutes).
- This includes water used for brushing teeth, making ice cubes, washing food, etc.
- As an alternative to boiling water, some commercially available home water filtration units are considered effective against cryptosporidium.
- While using bottled water might appear as an alternative, it is not routinely tested for cryptosporidium and caution should be exercised when selecting a product. Contact the bottler for details on processing.
- The decision to implement the preceding suggestions should be made in conjunction with a health care provider.
- When in restaurants or other public facilities, avoid tap water, ice cubes and any other beverage that is not canned or bottled.
- Make sure that eating and cooking materials washed in tap water are thoroughly dry before they are used.
- Avoid swallowing pool or bath water.
Where can I get more information?
Contact your doctor, the Southern Nevada Health District, Office of Epidemiology at (702) 759-1300 or the Office of HIV/AIDS at (702) 759-0702.
You may also contact the Department of Environmental Quality, Drinking Water Division at (801) 536-4205, or listen to the prerecorded information provided by the National Center for Infectious Diseases on its VoiceCom number at (404) 330-1242.
Visit the Centers for Disease Control and Prevention’s Healthy Swimming webpage for more information about “Crypto” at aquatic facilities.
(702) 759-1039 or (702) 759-0889
Updated on: August 17, 2018