Up to nearly ten percent of Americans may be infected with brain parasites from undercooked meat. One example is the brain-invasive pork tapeworm, which is the most common cause of adult-onset epilepsy. Allergenic fish worms found in nearly two-thirds of retail fish tested can trigger allergic reactions in sensitive individuals. Cheese may contain mites and maggots (“cheese skippers”). Nearly 95% of tested retail U.S. beef (including burgers) have been found infested with parasites. The meat industry has responded to this problem by feeding arsenic to chickens and pigs to reduce the parasite load.

Topic summary contributed by Anthony L. Zacchino.
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Watch videos about parasites

  • Cheese Mites and Maggots
    Cheese Mites and Maggots
    Cheese manufacturers use spider-like insects and fly larvae to impart particular flavors and aromas to certain cheeses.
  • Avoiding Epilepsy Through Diet
    Avoiding Epilepsy Through Diet
    Avoiding pork tapeworm parasites (cysticercosis) is not as easy as just avoiding pork.
  • Pork Tapeworms on the Brain
    Pork Tapeworms on the Brain
    Neurocysticercosis, infection with pork tapeworm larvae brain parasites, is an increasingly serious public health problem in the United States, potentially causing headaches, dizziness, seizures,...
  • Allergenic Fish Worms
    Allergenic Fish Worms
    The role of a parasitic worm in allergic reactions to chicken and fish.
  • What’s in a Burger?
    What’s in a Burger?
    Cleveland Clinic pathologists dissect fast food burgers to see what's inside.
  • Arsenic in Chicken
    Arsenic in Chicken
    The poultry industry feeds their birds millions of pounds of arsenic-containing drugs every year.
  • Brain Parasites in Meat
    Brain Parasites in Meat
    What percentage of U.S. lambs are infested with toxoplasma parasites?
  • USDA Parasite Game
    USDA Parasite Game
    What percentage of retail beef samples are infested with sarcocystis parasites?
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