Screwworm Eradication Program

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Screwworm Eradication Program

• 4-H Veterinary Science
• Extension Veterinary Medicine 
• Texas AgriLife Extension Service
• College of Veterinary Medicine and Biomedical
  Science
• Texas AM System
• http//aevm.tamu.edu

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Objectives

• Discuss the eradication of screwworms from the
  U.S.
• Understand that health regulations are health
  management practices used to prevent the spread
  of the disease
• Understand that control of disease can lead to
  eradication

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Screwworms

• Parasite
• Effect livestock and other warm-blooded animals
• Rare, but can affect people

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The Pest

• Adult stage
• 2x bigger than housefly
• Orange eyes
• Blue-gray or gray body
• 3 dark stripes down body
• 31 day lifespan
• 400 eggs at a time
• 2,800 during its life

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Larvae

• Hatch in 12 hours
• Eat raw flesh (flesh-eating)

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Life Cycle
Adult flies mate
Female lays eggs in open wound
Adult flies emerge from soil
Larvae hatch and feed on tissue
Larvae drop to ground and become pupae
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Life Cycle
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Infestations

• Animals most at risk are during
• Docking
• Dehorning
• Castration
• Navels of Newborn
• Minor cuts
• Tick bites

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Infestations

• Symptoms
• Foul smelling odor
• Wound oozing dark liquid
• Prompt action can make sure there is no outbreak
  like in 1950s

Photos by UC Davis Veterinary School of Medicine
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• If you suspect screwworms
• Collect a sample in a screwworm kit
• Mail to
• USDA State-Federal Diagnostic Lab4501
  Springdale RoadC/O GMF Postage-Due UnitAustin,
  TX 78714-9998