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Coenurosis is a parasitic infection that results when humans ingest the eggs of dog tapeworm species ''Taenia multiceps'', ''T. serialis, T. brauni,'' or ''T. glomerata.'' It is important to distinguish that there is a very significant difference between intestinal human tapeworm infection and human coenurosis. Humans are the definitive hosts for some tapeworm species, the most common being ''T. saginata'' and ''T. solium'' (pork and beef tapeworms). This means that these species can develop into full grown, reproductively capable adult worms within the human body. People infected with these species have a tapeworm infection. In contrast, the four species that cause human coenurosis can only grow into mature, reproductively capable worms inside their definitive hosts, canids such as dogs, wolves, foxes and coyotes. Humans who ingest eggs from any of these four species of ''Taenia'' become intermediate hosts, or places where the eggs can mature into larvae but not into adult worms. When humans ingest these eggs, the eggs develop into tapeworm larvae that group within cysts known as coenuri, which can be seen in the central nervous system, muscles, and subcutaneous tissues of infected humans. People with coenurosis do not develop a tapeworm infection because the larvae of coenurosis-causing parasites cannot develop into worms inside of humans. ==History of Discovery== Because this disease so rarely occurs in humans, it took a long time for it to become recognized within the population, and species differentiation among the four different types is still somewhat difficult. Many cases of coenurosis probably existed years before it was recognized or discovered, but the first cases to be diagnosed were as follows: * ''T. multiceps'': Diagnosed for the first time in 1913 in Paris, when a man presented symptoms of CNS nerve degeneration. He had convulsions and trouble speaking/ understanding speech. During his autopsy, two coenuri were found in his brain. * ''T. serialis'': In 1933 a French woman was proven to have coenurosis when the cyst that had been growing under her skin was extracted from her subcutaneous tissue and fed to a dog, which later developed tapeworm infection due to T. serialis. * ''T. brauni'' is endemic only in Africa, and the first reported case of African coenurosis (which was probably this particular species) was discovered by Fain and colleagues in 1956. * ''T. glomerata'': Even now, it is unclear whether this species is responsible for coenurosis in parts of Africa, but it is thought to be. The first reported case caused by this species occurred in Nigeria in 1919.〔〔http://web.gideononline.com/web/epidemiology/country_info.php?source=&country_id=G100&disease_id=10450&country_name=%3C%20Worldwide%20%3E%20@#〕 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「Coenurosis in humans」の詳細全文を読む スポンサード リンク
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