| 翻訳と辞書 |
| Hymenolepis diminuta ： ウィキペディア英語版 |
Hymenolepis diminuta
''Hymenolepis diminuta'', also known as rat tapeworm, is a species of ''Hymenolepis'' tapeworm that causes hymenolepiasis. It has slightly bigger eggs and proglottids than ''H. nana'' and infects mammals using insects as intermediate hosts. The adult structure is 20 to 60 cm long and the mature proglottid is similar to that of ''H. nana'', except it is larger.
''H. diminuta'' is prevalent worldwide, but only a few hundred human cases have been reported.〔Lo CT, Ayele Y, Birrie H. Helminth and snail survey in Harerge region of Ethiopia with special reference to Schistosomiasis. Ethiop Med J 1989;27:73-83.〕〔McMillan B, Kelly A, Walkar JC. Prevalence of Hymenolepis diminuta infection in man in the New Guinea Highlands. Trop Geogr Med 1971;23:390-2.〕〔Mercado R, Arias B. Infections by Taenia sp and other intestinal cestodos in patients of consultorios hospitals and the public sector north of Santiago de Chile (1985–1995). Bol Chil Parasitol 1995:50:80-3.〕 Few cases have ever been reported in Australia, United States, Spain, and Italy. In countries such as Malaysia, Thailand, Jamaica, Indonesia, the prevalence is higher.〔Tena D, Pιrez Simón M, Gimeno C, Pιrez Pomata MT, Illescas S, Amondarain I, et al. Human infection with Hymenolepis diminuta : Case report from Spain. J Clin Microbiol 1998;36:2375-6.〕〔Marangi M, Zechini B, Fileti A, Quaranta G, Aceti A. Hymenolepis diminuta infection in a child living in the urban area of Rome, Italy. J Clin Microbiol 2003;41:3994-5.〕〔Kan SK, Kok RT, Marto S, Thomas I , Teo WW. The first report in Hymenolepis diminuta infection in Sabah, Malaysia. Trans R Soc Trop Med Hyg 1981;75:609.〕
== Life cycle ==
The cycle begins as arthropods ingest the eggs. Arthropods are then able to act as the intermediate host. When ingested, the eggs develop into cysticercoids. As shown in the CDC life cycle, oncospheres hatch and then penetrate the intestinal wall.〔CDC H. diminuta life cycle. Accessed online April 2009 at: http://www.dpd.cdc.gov/DPDx/HTML/ImageLibrary/G-L/Hymenolepiasis/body_Hymenolepiasis_il8.htm〕 Rodents can become infected when they eat arthropods. Humans, especially children, can ingest the arthropods as well and therefore become infected via the same mechanism. Rodents, especially rats, are definitive hosts and natural reservoirs of ''H. diminuta''. The intermediate hosts are the coprophilic arthropods (fleas, lepidoptera, and coleoptera). As the definitive host (rats) eats an infected arthropod, cysticercoids present in the body cavity transform into the adult worm. The resulting eggs are then passed through the stool. In recent findings, beetle-to-beetle transmission of ''H. diminuta'' can be seen via the feces. Additionally, more infections occur due to this mechanism of egg dispersal.〔Pappas, P. W., and A. J. Barley. 1999. Beetle-to-beetle transmission and dispersal of Hymenolepis diminuta (Cestoda) eggs via the feces of Tenebrio molitor. J. Parasitol. 85:384-385.〕
Image:H_diminuta_LifeCycle.gif|H. diminuta life cycle.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
■ウィキペディアで「Hymenolepis diminuta」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|