Echinococcosis and cysticercosis in Asia: evaluation of the modern technology for epidemiological study.

ABSTRACT

The recent emergence of zoonotic parasitic diseases of public health importance represents a growing global concern. Among zoonotic helminthic diseases, both echinococcosis and cysticercosis are the most serious diseases threatening human life. Neurocysticercosis (NCC) caused by ingestion of eggs of the pork tapeworm, Taenia solium, is spreading worldwide and not rare even in Muslim or Jewish communities. Alveolar echinococcosis (AE) caused by the proliferation of metacestodes of the fox tapeworm, Echinococcus multilocularis, is the most potentially lethal parasitic infection of the non-tropical northern hemisphere, whereas cystic echinococcosis (CE) caused by the proliferation of metacestodes of the dog tapeworm, E. granulosus, has rather a cosmopolitan distribution. As the life cycles of T. solium, E. multilocularis and E. granulosus are completed through predator-prey interactions, including humans, it is crucial to interrupt the cycle for control of these zoonotic cestodiases. Both NCC and CE are expected to be eradicable, since the principal life cycles of T. solium and E. granulosus are maintained between humans and pigs and between dogs and herbivorous domestic animals, respectively. In contrast, AE is perhaps not eradicable, since the life cycle of E. multilocularis is maintained between wild foxes and rodents. Modern technologies, including imaging, immunology and molecular biology, have been applied for epidemiological surveys. In the present review, we introduce such technologies applied in Japan, China and Indonesia, and point out the problems that need to be solved for control of these three zoonotic cestodiases.