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Fish Roundworm

Fish Roundworm

Diseased animal

Can I still use the animal Yes, Take safety precautions
Commonly infected wildlife Fish
Is this animal infected
  • Infected fish have worms that are:
    • Often free in the fish's body cavity
    • 1/16"-1/8" long, less than 1/2" wide
    • White in color
    • Often in a coil shape
Can I get it Yes
  • By consuming raw or undercooked fish
  • Caution: Some people may develop allergic reactions after eating these worms
How bad can it get

Moderate risk

Beware: May require medical attention
How can I protect myself and others
  • Gut and process fish immediately to stop worms from moving into the muscle
  • Kill worms in the muscle:
    • Cook fish to 165°F for 10 minutes or
    • Freeze at -15°F for seven days, especially when the fish will be prepared for sushi
Symptoms in humans
  • Occur within hours of eating infected fish
    • Severe stomach pain
    • Nausea and vomiting
  • Worms may enter the intestine 1-2 weeks after infection
    • Surgical removal may be necessary if worms burrow into the intestinal wall
    • Worms are occasionally coughed up
  • Seek medical advice if you become ill after eating raw or undercooked fish
Is it safe for pets Yes, if the fish is well cooked (worms cannot survive in pets for long)
What causes it
  • A roundworm called Anisakis simplex
  • Commonly known as herring worm