Portal de Periódicos da CAPES

ON THE LUNG FLUKES CAUSING HUMAN PARAGONIMIASIS

1969; Volume: 10; Issue: 1 Linguagem: Inglês

10.2149/tmh1969.10.8

2186-1803

I. Miyazaki,

Helminth infection and control

In this paper the author wishes to summarize the lung flukes, which cause human paragonimiasis or which are suspected to infect humans not only in Asia but also in America and in Africa.In Asia, more than 20 species were reported in literature, of which 17 species are regarded as valid (Table 1).Since the author found Paragonimus ohirai in 1939, 14 species have been recorded in Japan, China and Thailand during past 30 years.Recently four species-P.siamensis, P. bangkokensis, P. harinasutai and P. sadoensis -were found by the author and his co-workers chiefly in Thailand.From medical point of view, P. westermani is most important widely occurring in Asia ; the author reconfirmed this species from South-east Asia to USSR.Another two species were recently proved to be the human parasite ; i. e. P. skrjabini (syn.P. szechuanensis Chung et Ts 'ao, 1962) was removed from human body on the mainland of China by Chung et al. (1962), and P. heterotremus (syn.P. tuanshanensis Chung et al., 1964) was from a boy in Thailand by Miyazaki and Harinasuta (1966).In addition, another species such as P. miyazakii, P. sadoensis, P. bangkokensis and P. harinasutai seem to have possibility of human infection, since their crab hosts are not infrequently eaten uncooked or pickled by inhabitants.In Japan five species are known, of which only P. westermani was removed from human body.The main source of human infection with this fluke is a big crab, Eriocheir japonicus.The metacercaria is mainly parasitic in the gill vessel and in the muscle of the crab.Another source of infection is a small crab, Potamon dehaani, which harbors not only P. westermani but also P. miyazakii and P. sadoensis.Because this crab is sometimes eaten uncooked by people, the latter two species are also suspected to infect humans.P. miyazakii parasitizes sev eral kinds of mammals such as the weasel, the martens, the wild boar and the dog.Besides, the fluke was proved by experiment to be able to mature in the albino rat, the Norway rat, the rabbit and the cat.Its first intermediate host is a very small snail, Bythinella nipponica, which liv es in mountain streams.The second intermediate host of the fluke is the above-mentioned crab, Potamon dehaani, which is also distributed in mountainous area.Metacercariae parasitic in this crab are mostly P. miyazakii and rarely P. westermani at present, but formerly those of the former were long confused with the latter by previous investigators.P. sadoensis was most recently found on Sado Island, Niigata Prefecture, and was found to be parasitic in the weasel and the cat.The fluke was experimentally proved to parasitize the dog, the albino rat, the wild mouse, the house rat, the Norway rat, the