Transmission

 

Humans can acquire echinostome infections by eating raw mollusks, fish, crustaceans, and amphibians (e.g. snails, tadpoles) and using night soil for fertilizer, which releases eggs into water habitats. 

 

Clinical Presentation in Humans

 

It is difficult to assess morbidity and mortality due to echinostomiasis because of a prolonged latent phase, short acute phase, asymptomatic presentations, and similar clinical symptoms as other intestinal helminthiasis. Although usually asymptomatic, depending on the parasite load, different clinical symptoms can be presented.  Light infections can cause anemia, headache, gastric pain, and loose stools.  Heavy infections can cause abdominal pain, emaciation, weakness, anemia, profuse watery diarrhea, hemorrhage, edema, and anorexia (Graczyk and Fried, 1998).

 

Diagnostic tests

 

To diagnose echinostomiasis, an examination of fecal specimens can be used to find characteristic ellipsoidal, yellow to yellow-brown eggs (size varies among species). 

 

E. ilocanum egg

(from http://www.cdfound.to.it/HTML/eilo1.htm)

 

Speciation of the trematode can be done based on morphology after anthelmintic treatment.  One study also used the ELISA method to detect anti-Echinostoma caproni immunoglobulins in mice (Gracyzk and Fried, 1994).