Food Poisoning Health (cont.)

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Parasitic Symptoms

Parasites rarely cause food poisoning. When they do, they are usually swallowed in contaminated or untreated water and cause long-lasting but mild symptoms.

  • Giardia (beaver fever): Causes mild illness with watery diarrhea often lasting one to two weeks. It is transmitted by drinking contaminated water, often from lakes or streams in cooler mountainous climates.
  • The infection can also be spread from person to person by food or other items contaminated with feces from an infected person.
  • Cryptosporidium: Causes moderate illness with large amounts of watery diarrhea lasting two to four days. May become a long-lasting problem in people with poor immune systems (such as people with kidney disease or HIV/AIDS or those on chemotherapy for cancer). It is transmitted by contaminated drinking water.
  • Toxoplasma: The CDC estimates that more than 60 million people in the U.S. carry the Toxoplasma parasite, but few have symptoms because the immune system keeps the parasite from causing illness. When it does cause disease, symptoms include headache, blurred vision, and eye pain. It is transmitted by eating undercooked or raw meat, contaminated water, or contact with contaminated cat feces. Pregnant women and those with compromised immune systems infected with Toxoplasma can have severe health complications.
  • Cyclospora: This parasite causes watery diarrhea, and explosive bowel movements. Other symptoms include loss of appetite, weight loss, stomach cramps/pain, bloating increased gas (flatulence), nausea, and fatigue. Symptoms may last from a few days to more than a month, and can relapse. Cyclospora is spread by people ingesting food or water contaminated with the parasite.
Medically Reviewed by a Doctor on 8/12/2013

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