Demodex Mites – An invisible world

Rosacea is a relatively common inflammatory skin disease, which affects about 3% of the world population. The progress of the disease includes various clinical stages and it appears on the central part of the face, mainly the cheeks, nose and chin. Rosacea usually presents after the age of 30, and it is more prevalent among women, while in men it is more severe.

Despite the fact that the pathogenetic mechanisms of rosacea are not known, various causative factors have been proposed. A large number of studies have been conducted in the past decades to examine the possible correlation between the pathogenesis of rosacea and the presence of certain microorganisms or bacteria, which exist on or in the skin.

Many scientists agree that possible Demodex mites develop, in particular Demodex folliculorum mites, which are among the approximately 100 different species that exist. The human skin may host two species of Demodex mites. It is also worth noting that the extent of Demodex colonisation in the human population is high (20 – 80%) and it increases with the age, reaching up to 100% in elderly people, as mite density starts to rise in the sixth decade of life until its stabilisation.

According to the results of a large number of studies, these mites, which host bacteria, may play a significant pathogenetic role in rosacea, on the one hand when present in large quantities and on the other hand because of an imbalance of the immune mechanism.

Furthermore, Demodex mite infestation usually remains asymptomatic, further intensifying the problem of non-diagnosis. However, as I have realised through my long and extensive experience with rosacea patients, it is of utmost importance to perform the special examination for the detection of the mite so that to provide an effectively treatment for the management of rosacea.

This is the reason why in I.Q. – Intensive Quality – Dermatology Clinics direct examination to detect Demodex folliculorum is performed. The examination is performed in the special microbiology laboratories of the clinics and within ten minutes it is determined whether the mite is there or not.

Depending on the laboratory findings, the appropriate treatment regimen is recommended with special miticides, such as crotamiton and permethrin. In some cases phototherapy is also used in combination, which has double action on Demodex folliculorum. More specifically, with the red light spectrum (633 nm) anti-inflammatory action is achieved, i.e. reduction of inflammation, while with the blue light spectrum (415 nm) anti-bacterial action is achieved, as it acts against the mites’ bacteria. Therefore it is possible to manage rosacea effectively.




Baldwin HE. Diagnosis and treatment of rosacea: state of the art. J Drugs Dermatol. 2012;11(6):725–730.

Del Rosso JQ. Advances in understanding and managing rosacea: Part 1. connecting the dots between pathophysiological mechanisms and common clinical features of rosacea with emphasis on vascular changes and facial erythema. J Clin Aesthet Dermatol. 2012;5(3):16-25.

Elston, D. M. (2010). Demodex mites: facts and controversies. Clin Dermatol 28, 502–504.

Jarmuda S, O’Reilly N, Zaba R, et al. Potential role of Demodex mites and bacteria in the induction of rosacea. J Med Microbiol 2012;61:1504-1510.

Zhao YE, Wu LP, Peng Y, et al. Retrospective analysis of association between Demodex infestation and rosacea. Arch Dermatol2010;146(8):896-902.