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Cryptosporidiosis: Facts, Treatment and Prevention

  • Synopsis: Published: 2015-06-28 (Revised/Updated 2017-06-25) - Information regarding Cryptosporidiosis (crypto), a form of disease caused by microscopic germs with a common symptom of watery diarrhea. For further information pertaining to this article contact: Thomas C. Weiss at Disabled World.

Cryptosporidium is a genus of apicomplexan protozoans. Cryptosporidium is a microscopic parasite that causes the diarrheal disease cryptosporidiosis. Both the parasite and the disease are commonly known as "Crypto." A number of Cryptosporidium species infect mammals. In humans, the main causes of disease are C. parvum and C. hominis (previously C. parvum genotype 1). C. canis, C. felis, C. meleagridis, and C. muris can also cause disease in humans.

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Quote: "The symptoms of cryptosporidiosis usually start within 2-10 days after a person has become infected with the parasite. The most common symptom of cryptosporidiosis is watery diarrhea."

Cryptosporidiosis or, 'crypto,' is a form of disease that causes a person to experience watery diarrhea. It is caused by microscopic germs; parasites called, 'Cryptosporidium.' While crypto may affect anyone, some groups are likely to develop more serious illness. For those with weakened immune systems, symptoms may be severe and might lead to life-threatening illness. Examples of people with weakened immune systems include people with AIDS, people with inherited forms of diseases that affect their immune system, as well as transplant and cancer patients who are taking certain immunosuppressive medications.

The symptoms of cryptosporidiosis usually start within 2-10 days after a person has become infected with the parasite. The most common symptom of cryptosporidiosis is watery diarrhea. Additional symptoms may include the following:

Symptoms of cryptosporidiosis generally begin 2 to 10 days (average 7 days) after becoming infected with the parasite. The most common symptom of cryptosporidiosis is watery diarrhea. Symptoms include:

  • Fever
  • Nausea
  • Vomiting
  • Weight loss
  • Dehydration
  • Stomach pain or cramps

Interestingly, some people with crypto will experience no symptoms whatsoever. The symptoms people do experience commonly last for a week or two; at least in people with healthy immune systems. On occasion, people might experience a recurrence of symptoms after a short period of recovery before the illness ends. The symptoms might come and go for up to a month.

Even though a person's small intestine is the place most commonly affected, in immunocompromised persons cryptosporidium infections could potentially affect additional areas of a person's respiratory or digestive tract. People with weakened immune systems could develop chronic, serious, or even fatal illness. Examples of people with weakened immune systems include:

  • People with AIDS
  • People with inherited diseases that affect their immune systems
  • Transplant and cancer patients who are taking certain immunosuppressive medications

The risk of developing severe disease might differ, depending upon each person's degree of immune suppression.

Diagnosing and Detecting Cryptosporidiosis

A diagnosis of cryptosporidiosis is achieved through examination of a person's stool sample. Due to the fact that detection of cryptosporidium may be difficult, a person might be asked to submit a number of stool samples over a period of several days. Most of the time, stool specimens are examined through a microscope using different techniques such as direct fluorescent antibody (DFA), acid-fast staining, or enzyme immunoassays for detection of cryptosporidium antigens.

Molecular methods such as polymerase chain reaction (PCR) are increasingly used in reference diagnostic laboratories because they may be used to identify cryptosporidium at the species level. Tests for cryptosporidium are not regularly performed in most laboratories. Due to this fact, health care providers should specifically ask for testing for the parasite.

Infection Sources and Risk Factors

Crypto lives in the intestines of infected animals or people. An infected animal or person sheds cryptosporidium parasites in their stool. Millions of crypto parasites may be released in a bowel movement from an infected person or animal. Shedding starts when the symptoms begin and may last for weeks after the symptoms end. A person may become infected after accidentally swallowing the parasite. Crypto may be found in food, soil, water, or on surfaces that have become contaminated with the feces of an infected animal or person. Crypto is not spread by contact with blood, although it may be spread by:

  • Swallowing water or beverages contaminated by stool from infected animals or people
  • Swallowing recreational water contaminated with crypto; recreational water may be contaminated with feces or sewage from animals or people
  • Placing something in your mouth, or accidentally swallowing something, that has come in contact with the stool of an animal or person who is infected
  • Consuming uncooked food contaminated with crypto; all vegetables and fruits you plan to eat raw should be thoroughly washed with uncontaminated water

A person might also touch their mouth with contaminated hands. Hands can become contaminated through a number of activities. These activities may include the following:

  • Changing diapers
  • Caring for a person who is infected
  • Handling an infected animal such as a calf or cow
  • Touching surfaces such as bathroom fixtures, toys, diaper pails or changing tables that have been contaminated by stool from an infected person

People with increased exposure to contaminated materials are at increased risk of infection. These people may include the following:

  • Childcare workers
  • International travelers
  • People who handle infected cattle
  • Parents of children who are infected
  • Children who attend childcare centers
  • People who swallow water from contaminated sources
  • People exposed to human feces through sexual contact
  • People who provide care for others with cryptosporidiosis
  • People who drink from untreated, shallow and unprotected wells
  • Hikers, campers and backpackers who drink unfiltered and untreated water

Contaminated water might include water that has not been filtered or boiled, as well as contaminated recreational water sources. A number of community-wide outbreaks of cryptosporidiosis have been linked to drinking municipal water, or recreational water contaminated with cryptosporidium.

Cryptosporidium parasites are found in every region of America and around the world today. Travelers to developing countries might be at increased risk for infection because of poorer water treatment and food sanitation, although cryptosporidiosis happens all over the world. In America, an estimated 748,000 new instances of cryptosporidiosis happen every single year. Once infected, people with decreased immunity are at greatest risk for severe disease. The risk of developing severe disease may differ depending upon each person's degree of immune suppression.

Treating Cryptosporidiosis

The majority of people who have healthy immune systems will recover without treatment. Diarrhea can be managed by drinking plenty of fluids to prevent dehydration. People who are in poor health, or who have weakened immune systems, are at increased risk for more prolonged and severe illness. Pregnant women and young children might be more susceptible to dehydration resulting from diarrhea and should drink plenty of fluids while they are ill. Quick loss of fluids from diarrhea may be particularly life-threatening to babies. Due to this, parents should communicate with their health care providers about fluid replacement therapy options for infants.

Anti-diarrheal medications might help to slow down diarrhea, although a health care provider should be consulted before these medications are taken. Nitazoxanide has been approved by the Food and Drug Administration (FDA) for treatment of diarrhea caused by cryptosporidium in people who have healthy immune systems and is available with a prescription. The effectiveness of nitazoxanide in people with weakened immune systems remains unclear.

People who are HIV-positive who suspect they have cryptosporidiosis need to contact their health care provider. For people with AIDS, anti-retroviral therapy that improve a person's immune status will also decrease or even eliminate symptoms of cryptosporidiosis. Even if a person's symptoms disappear; however, cryptosporidiosis is often times not curable and the symptoms might return if the person's immune status worsens.

Crypto and Practicing Good Hygiene

Hand washing is vital; wet your hands with clean running water and apply soap. Lather all surfaces of your hands and scrub for at least 20 seconds. Rinse with clean running water and dry with a clean towel or air-dry. It is important to wash your hands:

  • After using the toilet
  • Before preparing or consuming food
  • After handling an animal or its stool
  • After gardening, whether or not you wore gloves
  • Before and after caring for a person who is ill with diarrhea
  • After changing diapers or cleaning a child who has used the toilet

It is important to note that alcohol-based hand sanitizers do not effectively kill cryptosporidium. At childcare centers it is important to exclude children who are ill with diarrhea from childcare settings until their diarrhea has stopped. While you are at the swimming pool, do not swallow the water and take children on bathroom breaks every hour, or check their diapers every half-hour or hour. Protect other people by not swimming if you are ill with diarrhea.

Facts: Cryptosporidium

Cryptosporidium (pronounced krip-toe-spo-rid-ee-um) is a parasite that can live inside the intestines of humans, farm and wild animals, and pets.

  • The source of Cryptosporidium is animal or human fecal waste.
  • Cryptosporidium can form a protective shell, allowing it to survive under harsh conditions.
  • Cryptosporidium can only be seen with a microscope; over10,000 of them would fit on the period at the end of a sentence.
  • Cryptosporidium has been found in water, soil, and food, after contamination with fecal waste. Unwashed hands can also carry Cryptosporidium following fecal contact.

Statistics: Cryptosporidium

  • Cryptosporidiosis was first recognized as an illness in 1976.
  • The exact number of people who get cryptosporidiosis each year is currently unknown.

Related Information:

  1. Water Safety in the Event of an Emergency - Thomas C. Weiss - (2011-03-15)
  2. Human Intestinal Worms - Deworming and General Information - Information on common types of worms humans can be infected with, includes information on signs and symptoms as well as treatment options for worms - Ian Langtree
  3. Screw Worms and the Spread of Disease - Thomas C. Weiss - (2015-01-04)

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