Cryptosporidium Parvum


Cryptosporidium parvum can infect the intestinal tract of 45 vertebrate species. It causes a parasitic disease called cryptosporidiosis. Risk groups are children under the age of 2 years, travelers, and animal handlers

Cryptosporidium parvum

Cryptosporidium Parvum is most resistant to disinfectants when in oocyst’s stage. This is the stage when the parasite has a thick wall and is shed in the feces of contaminated people. At this stage, Cryptosporidium Parvum contaminates food, drinks, swimming pool, or other outdoor water.

Cryptosporidium parvum transmission

Reservoirs & Transmission

Cryptosporidium parvum reservoirs

The illness usually starts a week or a little longer after a person eats or drinks Cryptosporidium in food or water.



Cryptosporidium parvum symptoms

Cryptosporidium parvum may cause extremely large amounts of diarrhea when an individual swallows contaminated food, drinks, contaminated swimming pool water or other outdoor water. The amount of body fluid lost from this illness can be dangerous for anyone. The diarrhea can become even more severe and last a long time. The diarrhea can last  permanently, or the infection can spread to the liver and lungs. Once the infection is located in the lungs, there is a risk of lethal outcomes.


Susceptible Populations

Anyone can be affected by Cryptosporidiosis. However, the most severe cases have been linked to immunocompromised people. At increased risk are people in the same household if there is among them one with Cryptosporidiosis, workers at day-care, travelers to endemic regions, and health care personnel.

Prevention/ Food Handling/ Hand Washing

Separate Raw and Cooked: Use separate cutting boards, plates, and utensils for raw (uncooked) produce and raw (uncooked) meat, poultry, seafood, and eggs. Keep meat, poultry, seafood, and eggs separate from all other foods while shopping, and in the refrigerator.

Cook Thoroughly and Keep Food at Safe Temperature: Only a food thermometer can make sure meat, poultry, fish, and casseroles are cooked to a safe internal temperature. For example, internal temperatures should be 145°F or 63°C for whole meats (allow the meat to rest after cooking for 3 minutes at least) and fish, 160°F or 71°C for ground meats, and 165°F or 74°C for all poultry. Eggs should be cooked until the yolk is firm.

Chill: Use appliance thermometers to be sure your refrigerator is at or below 40ºF or  4°C and your freezer is 0ºF (-17.78°C) or below. Between 40ºF or 4°C and 140ºF or 60°, C is the Danger Zone, when bacteria can multiply rapidly. Generally, the more bacteria, the more likely someone will get sick. Most refrigerators have just a colder/ warmer adjustment, so the only way to know is to put a thermometer inside.

Hand Washing

  • Before, during, and after preparing food
  • Before eating food
  • Before and after caring for someone at home who is sick with vomiting or diarrhea
  • Before and after treating a cut or wound
  • After using the toilet
  • After blowing your nose, coughing, or sneezing
  • After touching an animal, animal feed, or animal waste
  • After handling pet food or pet treats
  • After touching garbage
  • Use Hand Sanitizer When You Can’t Use Soap and Water. Sanitizers can quickly reduce the number of germs on hands in many situations. Keep in mind, that sanitizers do not kill all types of germs. If your hands are visibly dirty, soap them and then use a sanitizer. They also might not remove chemicals, pesticides, and heavy metals from your hands.

The following information is an extract from the World Health Organization (2008). Foodborne Disease Outbreaks: Guidelines for Investigation and Control. Geneva, Switzerland, 2008