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Myiasis ( or ) is the parasitic infestation of the body of a live mammal by fly larvae (maggots) that grow inside the host while feeding on its tissue. Although flies are most commonly attracted to open wounds and urine- or feces-soaked fur, some species (including the most common myiatic flies, the botfly, blowfly and screwfly) can create an infestation even on unbroken skin and have even been known to use moist soil and non-myiatic flies (such as the common housefly) as vector agents for their parasitic larvae. Colloquialisms for myiasis include flystrike and blowfly strike, and the victim or the tissue may be described as fly-blown. The name of the condition derives from ancient Greek μυῖα (''myia''), meaning "fly". Because some animals (particularly domestic animals) cannot react as effectively as humans to the causes and effects of myiasis, such infestations present a severe and continuing problem for livestock industries worldwide, causing severe economic losses where they are not mitigated by human action.〔Otranto, Domenico. “The immunology of myiasis: parasite survival and host defense strategies.” Trends in Parasitology 17 (2001): 4.〕 Although typically a far greater issue for animals, myiasis is also a relatively frequent affliction of humans in rural tropical regions where myiatic flies thrive, and often may require medical attention to surgically remove the parasites.〔John, David and Petri, William. Markell and Voge’s Medical Parasitology: 9th Edition. Missouri: Saunders Elsevier, 2006. p. 328-334.〕 Myiasis varies widely in the forms it takes and its effects on the victims. Such variations depend largely on the fly species and where the larvae are located. Some flies lay eggs in open wounds, other larvae may invade unbroken skin or enter the body through the nose or ears, and still others may be swallowed if the eggs are deposited on the lips or on food.〔 == Signs and symptoms == How myiasis affects the human body depends on where the larvae are located. Larvae may infect dead, necrotic (prematurely dying) or living tissue in various sites: the skin, eyes, ears, stomach and intestinal tract, or in genitourinary sites.〔Ockenhouse, Christian, Samlaska, Curt, Benson, Paul, Roberts, Lyman, Eliasson, Arn, Malane, Susan, and Menich, Mark. “Cutaneous myiasis caused by the African tumbu fly.” Archives of Dermatology 126 (1990):199-202.〕 They may invade open wounds and lesions or unbroken skin. Some enter the body through the nose or ears. Larvae or eggs can reach the stomach or intestines if they are swallowed with food and cause gastric or intestinal myiasis.〔 Several different presentations of myiasis and their symptoms:〔 Nosocomial Myiasis refers to myiasis in a hospital setting. It is quite frequent, as patients with open wounds or sores can be infested if flies are present. To prevent nosocomial myiasis, hospital rooms must be kept free of flies. Human ophthalmomyiasis, both external and internal, has been caused by botfly larvae. 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「myiasis」の詳細全文を読む スポンサード リンク
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