Echinococcus granulosus

• Hydatid Disease
• final host
  • dog, fox, and other canids
• intermediate host
  • sheep most commonly affected
  • ox and horses

NB: can also affect man - zoonosis

• hydatids - the cyst form
  • develops from the ova
  • occur in the lung and liver
  • cysts are usually multiple
  • 5-10cm in diameter
  • contain a clear fluid with numerous scolices or "hydatid sand"
  • the small calcified lesions that are sometimes present in the liver of sheep may represent degenerate hydatid cysts
  • can be very prevalent in some geographical areas