Cryptosporidium Infection

Cryptosporidium Infection: Overview

Alternative names: Although the parasite Cryptosporidium causes the disease known as Cryptosporidiosis or Cryptosporidium infection, both the disease as well as the parasite are often referred to as "Crypto".

Cryptosporidium infests public water systems and can cause widespread outbreaks of severe diarrhea and cramps.  It has been found in water supplies throughout the United States, and the disease it causes can prove fatal for people with weakened immune systems.

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Most species of Cryptosporidium infect animals, but there are certain strains that can also infect humans.  The parasite is able to survive outside the host for long periods of time due to its protective outer shell, this makes it also extremely tolerant to chlorine disinfection.

Cryptosporidium parasites are found throughout the USA and all across the world.  Due to its resilience, Cryptosporidium is one of the leading causes of waterborne diseases affecting humans in America.

Incidence; Causes and Development; Contributing Risk Factors

In America more than 748,000 cases of Cryptosporidium infection occur yearly.

The infection is caused by a microscopic one-celled parasite referred to as Cryptosporidium.  After entering the host, these Cryptosporidia make their way to the small intestine and attach to the walls of the intestines where they multiply and at a later stage spread even further by leaving the host in massive numbers by being shed in its feces.  Shedding Cryptosporidia in the feces will commence as soon as the symptoms of diarrhea are experienced and can last for weeks even after the symptoms have stopped.

Infection can be caused by coming into contact with contaminated feces, or in other ways:

  • Ingesting contaminated water during swimming
  • Eating contaminated or uncooked food
  • Touching your mouth after being in contact with a contaminated object or surface
  • Close contact to infected people or animals

Because cryptosporidium can be found in soil, water and food, infections can occur quite easily through accidental ingestion.  Community-wide outbreaks are not uncommon and are mostly linked to drinking contaminated municipal water or coming into contact with recreational water like public swimming pools.

People who are more likely to be exposed to contaminated materials include:

  • Children attending daycare centers
  • Parents of infected infants and children
  • Teachers and childcare workers
  • Nurses and caretakers
  • Travelers, backpackers, campers and hikers
  • People who drink from untreated water sources
  • People working with cattle or other animal

Signs and Symptoms

Symptoms of Cryptosporidium infection generally surface within a week and can include the following:

  • Main symptoms

  • Other symptoms

    • Dehydration
    • Lack of appetite
    • Weight loss
    • Fever
    • Nausea and vomiting

These symptoms can last for up to 14 days and may randomly reappear for up to a month.

Diagnosis and Tests

Tests for Crypto are not routinely performed by labs and must therefore be specifically requested by a doctor.  Stool samples are examined to detect Cryptosporidium infection.

Tissue histopathology can also be used as a method of detection where the crypto parasites can be identified in the lumen or lining the epithelial surfaces.

Treatment and Prevention

In cases where the infected individual has a healthy immune system, the disease will be self-limiting, only causing diarrhea for up to a few days.  However, those with a compromised immune system such as those suffering from HIV/AIDS are at greater risk of being infected and will suffer more severe symptoms that may prove difficult to treat.

Although anyone can become infected, pregnant women and young children are often more susceptible to dehydration from diarrhea and should take great care to replenish their fluids while ill.

Patients with a healthy, uncompromised immune system can be prescribed the FDA-approved drug Nitazoxanide for the treatment of diarrhea caused by Cryptosporidium.  Other than that, they do not require any specific treatment.

General recommendations include:

  • Take in plenty of fluids to avoid dehydration
  • Avoid carbonated drinks and undiluted juice
  • Do not use medicine that prevents diarrhea or vomiting, unless it is recommended by a medical doctor
  • Avoid foods high in sugar or fat

Cryptosporidium infection is highly contagious and great care should be taken not to spread the parasite to others.  Preventative measures that help to avoid transmission of the parasite include:

  • Practicing good hygiene (washing hands, using sanitizer)
  • Rinsing and thoroughly washing all fruits and vegetables before consumption
  • If traveling in a developing country, avoid eating uncooked foods
  • Drink purified water only (this includes ice cubes)
  • Limit swimming activities in public swimming pools, lakes, streams or stagnant water
  • Avoid any exposure to fecal matter
  • Exclude infected people from childcare and schools or food industries

These precautions are especially important for those with a compromised immune system.

Complications; Seek medical attention if...

Complications can occur after prolonged Cryptosporidium infection.  These include malnutrition, severe dehydration, weight loss, and bile duct, gallbladder or liver inflammation.

Consider seeking medical attention if any of the following occur:

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