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
- Travelers
- Men who have sex with men
- The immunecompromised
- Close personal contacts of infected individuals
- Families
- 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:
- Man
- Cattle
- 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:
- Person-to-person
- Fecal-oral
- Animal-to-person
- Waterborne
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
- Malnutrition
- Dehydration
- 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.
