Human Permanent Ectoparasites; Recent Advances on Biology and Clinical Significance of Demodex Mites: Narrative Review Article

<p><strong><em>Background:</em></strong> <em>Demodex</em> is a genus of mites living predominantly in mammalian pilosebaceous units. They are commonly detected in the skin of face, with increasing numbers in inflammatory lesions. Causation between <em>Demodex</em> mites and inflammatory diseases, such as rosacea, blepharitis, perioral and seborrhoeic dermatitis or chalazion, is controversially discussed. Clinical observations indicate a primary form of human <em>Demodex</em> infection. The aim of this review was to highlight the biological aspects of <em>Demodex</em> infestation and point out directions for the future research.</p><p><strong><em>Methods</em></strong><em>:</em><strong> </strong>We conducted a broad review based on the electronic database sources such as MEDLINE, PubMed and Scopus with regard to the characteristics of the <em>Demodex</em> species, methods of examination and worldwide epidemiology, molecular studies and its role in the complex human ecosystem.</p><p><strong><em>Results:</em></strong> <em>Demodex</em> mites are organisms with a worldwide importance as they act in indicating several dermatoses, under certain conditions. However, correlations between <em>Demodex</em> and other parasites or microorganisms occupying one host, as well as interactions between these arachnids and its symbiotic bacteria should be considered. There are few methods of human mites' examination depending on purpose of the study. Nevertheless, paying attention must be needed as polymorphism of <em>Demodex</em> species has been reported.</p><p><strong><em>Conclusion:</em></strong> Overall, the present review will focus on different aspects of <em>Demodex</em> mites’ biology and significance of these arachnids in human’s health.