

Hydatid Disease (Part IV)
The larval form of E. granulosus manifests itself as a cyst, called a hydatid cyst. The cyst is actually not a single larva, but a fluid filled balloon of tissue filled with large numbers of tiny larval forms, called protoscolices (sing. protoscolex). Each protoscolex has the potential, if ingested by a dog, of becoming an adult tapeworm in the intestines of a dog, where the cycle can start again. Note that dogs carry these worms without problems or symptoms. You cannot tell

Hydatid Disease (Part III)
Above is the life cycle of E. granulosus. Life is fine for all concerned if the pattern follows the red lines, However, if there's the detour to the blue lines--the accidental ingestion of an egg by a human instead of a sheep--then consequences ensue. Notice that the egg is shed in feces. Dog poop. Since this parasite is transmitted to humans via the all-too-common route of fecal-oral, good hygiene ( in theory) should prevent this. We all know that hand-washing, the most impo


Hydatid Disease (Part II) : How a tiny tapeworm larva makes you wicked sick (Gross picture alert)
Let's go back to the life cycle of Echinococcus granulosus, the cestode (tapeworm) that causes hydatid disease. (There are two types of people: Those who like studying parasite life cycles, and those who would rather suffer from the parasite. Guess which type we are here at PAZ.) Here is an adult Taenia solium tapeworm, (also known as the pork tapeworm, the kind you get from eating infested, undercooked pork) being extracted from a patient's intestines via endoscopy (this is