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Fascioliasis is an illness caused by Fasciola parasites, which are flatworms referred to as liver flukes. Two Fasciola species infect people: Fasciola hepatica, known as "the common liver fluke" and "the sheep liver fluke", is the most common. Fasciola gigantica is less common but can also infect people.

Transmission occurs through the consumption of uncooked aquatic plants (such as watercress) that are contaminated with infectious larvae (metacercariae). Transmission can also occur by ingesting contaminated water, e.g., by drinking it or by eating vegetables that were washed or irrigated with contaminated water. Infection is not transmitted directly from person to person.

Early (acute) symptoms of fascioliasis may include fever, nausea, vomiting, diarrhea, a swollen liver, liver function abnormalities, skin rashes, shortness of breath, and abdominal pain or tenderness. The chronic phase (after the parasite settles in the bile ducts) is marked by inflammation and hyperplasia and thickening of the bile ducts and gall bladder, leading to biliary lithiasis or obstruction. The symptoms of this phase, such as biliary colic, nausea, intolerance to fatty food, right upper quadrant pain, epigastric pain, obstructive jaundice, and pruritus, are the result of a blockage in the biliary tract and inflammation in the gall bladder. Inflammation of the liver, gallbladder, and pancreas can also occur.


  • Routine hand washing with soap and warm water.
  • Avoid eating uncooked watercress and other aquatic plants of wild or unknown origin, especially from grazing areas or places where the disease is known to be endemic.
  • Vegetables grown in fields that might have been irrigated with contaminated water should be thoroughly cooked.
  • Travelers to areas with poor sanitation should avoid food and water that might be contaminated.


School Exclusion Policy
Children with confirmed fascioliasis should be kept out of school or childcare until they are diarrhea and fever-free. Rules for the exclusion of sick children from school and childcare are outlined in the Texas Administrative Code, specifically Rule 97.7 for schools and Rule 746.3603 for childcare.

Recent Texas Trends
Fascioliasis became a notifiable condition in Texas in 2016. Reports of Fascioliasis cases have been rare.

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