The taxonomy, life cycle and pathology of Sarcoptes scabiei and Notoedres cati (Acarina, Sarcoptidae): A review in a Fennoscandian wildlife perspective

Mites constitute an old cosmopolitan group, abundant in various terrestrial and aquatic habitats of considerable environmental variations. The majority of mites are free-living, whereas some have evolved parasitic relationships with a variety of animals either as endo- or ectoparasites. The ectoparasitic and skin burrowing Sarcoptes scabiei and Notoedres cati, cause sarcoptic and notoedric mange among a variety of mammalian species, including humans. In a non-adequate host these mites lead to pseudo-scabies which is often self-curable. The aim of this review is to provide an overview of recent knowledge on the taxonomy, life cycles and pathology of these two mites, which are of relevance to Fennoscandian wildlife, by considering knowledge on transmission vectors, host immunology, and some documented outbreaks. These mites affect the health and survival of mammals in four ways; 1) skin tissue damages, 2) loss of body fluids, 3) allergic reactions and 4) secondary bacterial infections. A short-term effect of outbreaks is usually high mortality, and long-term effects vary from extinction to biased population structure to no effect at all. Red foxes are generalist predators that are important end-hosts for mites that develop disease depending on their immunity status, and transmit mites to other hosts. Outbreaks of mange may possibly have ecological consequences on a wider scale. In an endangered species, like the arctic fox or Eurasian lynx, loss of only a few individuals can be critical. It might be wise for management authorities to develop emergency plans to minimize consequences of outbreaks of sarcoptic or notoedric mange in threatened species such as the arctic fox and the lynx