Echinococcus

From Wikipedia, the free encyclopedia

Echinococcus
Scientific classification
Kingdom: Animalia Phylum: Platyhelminthes Class: Cestoda Order: Cyclophyllidea Family: Taeniidae Genus: Echinococcus
Species
Echinococcus granulosus Echinococcus multilocularis Echinococcus shiquicus Echinococcus oligarthrus Echinococcus vogeli Echinococcus ortleppi Echinococcus equinus

The genus Echinococcus includes six species of cyclophyllid tapeworms to date, of the family Taeniidae. Infection with Echinococcus results in hydatid disease, also known as echinococcosis

In humans, this causes a disease called echinococcosis. Latency can be up to 50 years, and is mostly found in South and Central America, the Middle East, China, and the West of the U.S.A. (eg. Arizona, New Mexico and California).

Echinococcosis is a zoonosis, human is a dead-end host. The usual hosts are predators, lions and dogs. Humans are infected with eggs. Larvae in various organs form the so called hydatid cyst. In normal hosts the hydatid cysts give rise to larvae, and their scolex is excreted in the stool. In human this does not happen, the cysts persist and grow for years without symptoms.

The cysts are regularly found in the liver (and every possible organ: spleen, kidney, bone, brain, tongue and skin) and are asymptomatic until their growing size produces symptoms or are accidentally discovered. Lesion of the cysts (spontaneus or iatrogenic eg. liver biopsy) threatens with anphylaxic shock.

Cysts are detected with ultrasound or CT. Antibodies can be detected with CF (complement fixation), ELISA, and various methods.