What is Cryptosporidium?
Cryptosporidiosis is a diarrheal disease caused by microscopic parasites, Cryptosporidium, that can live in the intestine of humans and animals and is passed in the stool of an infected person or animal. The parasite is protected by an outer shell that allows it to survive outside the body for long periods of time and makes it very resistant to chlorine-based disinfectants. During the past 2 decades, Cryptosporidium has become recognized as one of the most common causes of waterborne disease (recreational water and drinking water) in humans in the United States. The parasite is found in every region of the United States and throughout the world.
Both the disease and the parasite are commonly known as “Crypto.”
How is crypto spread?
You can become infected after accidentally swallowing the parasite. Cryptosporidium may be found in soil, food, water, or surfaces that have been contaminated with the feces from infected humans or animals. Crypto is not spread by contact with blood.
Crypto can be spread by:
- swallowing water or beverages contaminated with stool from infected humans or animals.
- eating uncooked food contaminated with Crypto. Thoroughly wash with uncontaminated water all vegetables and fruits you plan to eat raw.
- putting something in your mouth or accidentally swallowing something that has come into contact with stool of a person or animal infected with Crypto.
- swallowing recreational water contaminated with Crypto. Recreational water such as swimming pools, hot tubs, Jacuzzis, fountains, lakes, rivers, springs, ponds, or streams. It can be contaminated by sewage, and human or animal feces.
- touching your mouth with contaminated hands. Hands become contaminated through a variety of activities, such as touching surfaces (e.g., toys, bathroom fixtures, changing tables, and diaper pails) that have been contaminated by stool from an infected person, changing diapers, caring for an infected person, and handling an infected cow or calf.
Common symptoms of crypto include:
- Watery diarrhea
- Stomach cramps or pain
- Weight loss
Some people with Crypto will have no symptoms at all. While the small intestine is the site most commonly affected, Crypto infections could possibly affect other areas of the digestive tract or the respiratory tract.
Symptoms of crypto generally begin 2 to 10 days (average 7 days) after becoming infected with the parasite. In persons with healthy immune systems, symptoms usually last about 1 to 2 weeks. The symptoms may go in cycles in which you may seem to get better for a few days, then feel worse again before the illness ends.
Who is most at risk for infection with crypto?
- Children who attend day care centers, including diaper-aged children
- Child care workers
- Parents of infected children
- People who take care of other people with cryptosporidiosis
- International travelers
- Backpackers, hikers, and campers who drink unfiltered, untreated water
- People who drink from untreated shallow, unprotected wells
- People, including swimmers, who swallow water from contaminated sources
- People who handle infected cattle
Contaminated water may include water that has not been boiled or filtered, as well as contaminated recreational water sources (e.g., swimming pools, lakes, rivers, ponds, and streams). Several community-wide outbreaks of cryptosporidiosis have been linked to drinking municipal water or recreational water contaminated with Cryptosporidium.
Although crypto can infect all people, some groups are likely to develop more serious illness.
- Young children and pregnant women may be more susceptible to the dehydration resulting from diarrhea and should drink plenty of fluids while ill.
- If you have a severely weakened immune system (including persons with AIDS; cancer and transplant patients taking certain immunosuppressive drugs; and those with inherited diseases that affect the immune system, etc.) you are at risk for more serious disease. Your symptoms may be more severe and could lead to serious or life-threatening illness.
Cryptosporidium can be very contagious
To avoid spreading the disease to others infected individuals should wash their hands frequently with soap and water, especially after using the toilet, or changing diapers, and before eating or preparing food. If you think you may have crypto see your health care provider.
Your health care provider will ask you to submit stool samples to see if you are infected. Because testing for Crypto can be difficult, you may be asked to submit several stool specimens over several days. Tests for Crypto are not routinely done in most laboratories. Therefore, your health care provider should specifically request testing for the parasite.
What is the treatment for cryptosporidiosis?
Nitazoxanide has been FDA-approved for treatment of diarrhea caused by Cryptosporidium in people with healthy immune systems and is available by prescription. Consult with your health care provider for more information. Most people who have healthy immune systems will recover without treatment. Diarrhea can be managed by drinking plenty of fluids to prevent dehydration. Young children and pregnant women may be more susceptible to dehydration. Rapid loss of fluids from diarrhea may be especially life threatening to babies. Therefore, parents should talk to their health care provider about fluid replacement therapy options for infants. Anti-diarrheal medicine may help slow down diarrhea, but a health care provider should be consulted before such medicine is taken.
People who are in poor health or who have weakened immune systems are at higher risk for more severe and more prolonged illness. The effectiveness of Nitazoxanide in immunosuppressed individuals is unclear. HIV-positive individuals who suspect they have Crypto should contact their health care provider. For persons with AIDS, anti-retroviral therapy that improves immune status will also decrease or eliminate symptoms of Crypto. However, even if symptoms disappear, cryptosporidiosis is often not curable and the symptoms may return if the immune status worsens.
Photo courtesy of CDC/Dr. Edwin P Ewing, Jr.