Demodex follicle mite

This mite belongs to the Arthropoda phylum, Arachnida class, Acaridae family, Demodex family. It is also called Demodex mite because it parasitizes hair follicles. Its body shape is significantly different from other mites, being elongated and caterpillar-like, measuring 0.3 to 0.4 mm. It is a parasite specific to humans, and is prevalent on the face. When a large number of them parasitize due to long-term topical use of steroids, it causes acne-like demodex disease (follicular acne). D. brevis is also a parasite that parasitizes humans. It is said that all mammals have their own specific species of Demodex mites, and Demodex canis, which parasitizes dogs, is famous for causing severe skin disease.

[Kimito Uchikawa]

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

節足動物門クモ形綱ダニ目ニキビダニ科に属するダニ。毛包(もうほう)に寄生するため毛包虫ともよばれる。体形はほかのダニ類と著しく異なり、細長くイモムシ状で、0.3～0.4ミリメートル。ヒトに固有な寄生虫で、顔面に好発し、ステロイド剤長期外用などで多数寄生を生ずると、にきび様の毛包虫症（毛包性痤瘡(ざそう)）をおこす。ヒトにはほかにD. brevisが寄生する。すべての哺乳(ほにゅう)類には、それぞれに固有な種類のニキビダニ類があるとされ、そのうちイヌに寄生するイヌニキビダニは、激しい皮膚病をおこすことで有名である。

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