Demodex Test: How to Diagnose Demodex Mite Infection

demodex test

If you wonder if you have a Demodex infection or are looking for a straightforward explanation of how the Demodex mite test works, this article is probably what you are looking for. After a brief introduction about Demodex mites and their complications, this article fully explains the methods to diagnose this parasite.

Demodex Mites and Their Symptoms

Demodex is a genus of mites that lives predominantly near all mammals’ pilosebaceous units. So far, scientists have identified 65 species of them, among which folliculorum and Demodex Brevis are the only species that live on humans. They usually move between the skin’s surface and its depth. Demodex mites crawl with eight stubby legs clustered in their front third, spread through the skin’s pores, and fit deep into the follicles and sebaceous glands. These parasites tend to avoid the bright lights, spend most of their time hooked under the skin, and only come to the skin surface at night.

Although Demodex infestation usually remains asymptomatic, they may be responsible for exacerbating skin lesions when they grow in number. The symptoms usually occur when there are more than five mites per square centimetre of skin.

Demodex mites can aggravate, mimic or even cause the following concerns:

How to Diagnose a Demodex Mite Infection

Since they are only 0.1 – 0.4 mm long, observing and counting Demodex mites with the naked eye is impossible. Rather, scientists have designed indirect methods to track down, detect, and count them. Sampling and counting parasites under a microscope is a standard method employed in various studies. An online test, on the other hand, examines the severity of symptoms as well as the mites’ growth aiding factors using a questionnaire.

Each of these methods (microscopic Demodex diagnostic test and online quiz) has its pros and cons, which we will examine.

Demodex Microscopic Diagnostic Tests

  • Standardised Skin Surface Biopsy (SSSB)
  • Direct Microscopic Examination (DME)

Standardised Skin Surface Biopsy (SSSB):

SSSD is the gold standard technique for diagnosing Demodex infection, which is performed in the following steps:

  • Clients are guided not to clean the affected zone for at least 12 hours.
  • A standard surface area of 1 cm2 is drawn on a glass slide with a waterproof pen.
  • A drop of cyanoacrylate adhesive is put on the glass in the 1 cm2 area.
  • The adhesive containing surface is laid to the affected part of the skin.
  • Then removed gently after being allowed to dry (about 1 min).
  • After removing the side, the sample is clarified using a few drops of immersion oil and covered with a coverslip.
  • Demodex mites are counted under a lens with a magnification of × 40, × 100.
demodex test

Direct Microscopic Examination (DME)

DME is another valid microscopic test to detect demodex infection:

  • A drop of paraffin is placed on the slide and a drop on the client’s skin. (Potassium hydroxide may be used.)
  • Paraffin is spread on the skin to prevent the collected sample from slipping.
  • An area of 1 cm2 of the affected skin is squeezed between the thumb and index finger.
  • Then, fresh secretions of oil glands and skin scrapings are collected using the blunt end of a sterile scalpel. 
  • The sample is transmitted to a microscope slide, mixed with a drop of glycerine, then covered with a coverslip. 
  • Demodex mites are counted under a lens with a magnification of × 40, × 100.

The dermatologist diagnoses Demodex infection in both microscopic methods if the number of parasites exceeds 5 per square centimetre.

Demodex Online Diagnostic Test

Demodex Online Diagnostic Test is a questionnaire consisting of multiple-choice questions. These inquiries examine the symptoms of Demodex as well as the elements that assist them in growing. For example, pruritus, rosacea, and dermatitis are Demodex parasite infection symptoms that the online test measures. On the other hand, factors such as weak immune system, being old, poor mental status, etc., significantly impact the Demodex mites’ population. By examining all these factors in total and assigning different weights to the answers, this questionnaire examines the individual’s status in terms of Demodex infection. It provides the results in four tiers immediately after the test. The green colour, which indicates the low density of Demodex, is the most favourable condition, while yellow, red and purple indicate moderate, high and very high numbers of these parasites, respectively. Individuals with a high Demodex density would better seek a solution to control them abruptly.

Ungex products, including PDT and SDT, are specifically formulated to solve the Demodex-originated problems and even prevent them. Individuals with a moderate density of parasites would better stop Demodex from overgrowing by applying these products once a week.

Microscopic vs. Online Demodex Testing

Although counting Demodex mites under a lens sounds ultimately practical and convincing, the Demodex microscopic test has its drawbacks like other types of procedures. Some of the microscopic test challenges are as follows:

  • Requires great precision; the results may vary depending on technician skill.
  • Results vary based on light changes over the day. 
  • The result of the microscopic test can change in different types of skin (Oily skins carry more Demodex on the surface while in dry kinds, Demodex mites tend to hide in depth.)

In contrast, online testing does not have the shortcomings of microscopic testing, but it may seem unreliable because it is not based on observation. However, our studies in recent years have revealed that online testing accurately estimates the density of Demodex. This test is available anywhere in the world for free and helps all those who suffer from skin problems to evaluate their Demodex mite’s density.


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4 thoughts on “Demodex Test: How to Diagnose Demodex Mite Infection


    Hi I no I have some kind of mute on my body I feel them moving and they are in my hair and eyes all over me cannot sleep or do much at all I have copd bad Lungs and realy need help my doctor just had a little luck at me said nothing is on my skin I no this is not true please help me thank you

    • Sepideh Ghaffari says:

      Hi Miss Tracey,
      Sorry for the late reply. Demodex mites are microscopic parasites, so some dermatologists don’t that much attention to them since they are invisible to the naked eye. You can book a time to speak about your problem with our consultant here

      • Sepideh Ghaffari says:

        Hi Lela,

        Thanks for your comment. I have to add that Demodex mites are microscopic mites, so if you see them, they might be other mites or insects. Our products can help some other mites or insects to be removed too. You may read it here.

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