Infection Experiments in Man and Other Mammalian Hosts with Sparganum Stage of Oriental Diphyllobothrids

Abstract

The Sparganum larva of a diphyllobothrid (psaudophyllidean) cestode was first recovered from man in 1882 by Patrick Manson, who obtained a dozen of these ligulate worms from the perirenal fat of an Amoyese. The same year Scheube obtained similar material from a Japanese subject. Following these early cases numerous additional human infections were described from Japan and French Indo-China, the latter being almost if not entirely from the orbit. A few human cases have also been reported from Australia. These larvae have been consistently designated as “Sparganum mansoni”, after their discoverer. Meanwhile larvae indistinguishable from those recovered from the human host have been obtained from numerous vertebrates in the Orient, including frogs, snakes, birds and mammals. These, too, have commonly been referred to as “Sparganum mansoni”, although experimental feedings to dogs and cats of the larvae from human cases in Japan (Okumura's 1 material) have shown that the adult worms belong to 2 previously described species, Diphyllobothrium decipiens and D. cordatum, while similar experiments in French Indo-China (Joyeux and Houdemer 2 ) have produced adults of another species which these investigators have described as “Diphyllobothrium mansoni”.

During a period of more than 8 years the writer has collected adult diphyllobothrids from naturally infected dogs and cats and their wild relatives in China and has had placed in his hands for study a complete worm of the generic group from the intestine of a native Chinese in Shanghai. These Chinese worms have been diagnosed as belonging to the following species: Diphyllobothrium cordatum (Leuckart, 1863), Stiles and Hassall. 1926, (dog, Peking and Amoy); D. mansoni (Cobbold, 1883), Joyeux, 1927, (cat, Canton, Foochow, Peking); D. decipiens (Diesing, 1850), Chandler, 1925, (cat, wild-cat, leopard, Peking); D. ranarum (Gastaldi, 1854), Meggitt.