Cryptosporidiosis Fact Sheet

Cryptosporidium is a parasite that causes diarrhea

Cryptosporidium infections (cryptosporidiosis) have been reported in humans and a wide variety of animals such as cattle, dogs, and cats. Infected humans and animals shed the parasite in their feces (stool). As a result, Cryptosporidium can be found in any environment that is contaminated by the feces of infected humans or animals, as well as lakes, rivers, water reservoirs, and ground water contaminated by these surface waters. The parasite is highly resistant to chlorine, which is commonly used as a disinfectant in water treatment plants.

Transmission can occur by coming into contact with feces of infected humans or animals, including:

Consumption of contaminated water or food
Person-to-person contact, particularly in child care settings
Handling of infected pets or farm animals
Sexual activity that involves contact with feces

Symptoms appear 2 to 12 days after exposure to infected feces

Diarrhea
Stomach cramps
Fever
Nausea

Some infected people may have no symptoms. People with normal immune systems usually have symptoms for one to two weeks and then recover fully. However, people with weakened immune systems, such as cancer patients, organ transplant recipients, and HIV-infected persons, may have more severe diarrhea that can persist long enough to become life-threatening.

There is no specific treatment for cryptosporidiosis

Replacing fluid lost through diarrhea may be needed. Healthy people normally recover within two weeks. Patients with severe or long-lasting diarrhea should consult their doctor.

Tests are available to look for Cryptosporidium in feces and in water

The Environmental Protection Agency (EPA) requires that certain large water companies routinely test water for Cryptosporidium.

Cryptosporidiosis can be prevented

Avoid drinking untreated water from lakes, streams, springs, or any other untreated sources
.Boil any water of unknown quality for at least one minute before consumption (including water used in drinks and to make ice).
Avoid any direct contact with human or animal feces.
Wash hands after using the toilet, changing diapers, and before handling food or eating.
Wash hands after contact with or cleaning up after pets.
Wash hands after gardening or other direct contact with the soil.
Wash fruits and vegetables before eating them.
Avoid unpasteurized milk products.
Avoid swallowing water during swimming, even in public swimming pools.

People with weakened immune systems may want to take extra action to reduce the risk:

Boil water, or use certain filters or bottled water for all the water you drink including tooth brushing.
Check with your doctor to see if you should take any other measures to avoid cryptosporidiosis if you have a weakened immune system.

Maryland Department of Health & Mental Hygiene
Epidemiology & Disease Control Program
April 2008

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