Demodex mites are the most common parasites found on human skin. They primarily reside in hair follicles, meibomian glands, and sebaceous glands of the eyes, and can trigger eye-related symptoms such as dry eyes, itchy eyes, and a pronounced foreign-body sensation. At present, it has been established that two types of Demodex mites parasitic in humans: Demodex follicle mite and Demodex sebum mite. Both types can induce various ocular surface diseases, including blepharitis, meibomian gland dysfunction, corneal disease, pterygium and ocular rosacea. However, due to subjective and objective factors, such as similar disease symptoms, omission of examination and a lack of awareness, these diseases are easy to misdiagnosis and underdiagnosis. Demodex mites exhibit a highly degree of age-dependence and can be detectd in asymptomatic adults. Consequently, the pathogenicity of Demodex mites has been a subject of debate. Existing studies have shown that Demodex mites can cause diseases through direct injury, by inducing hypersensitivity reactions, and by acting as carriers for bacteria. Effective means are available for detecting Demodex mite infections. Treatement options include warm compresses, eyelid cleaning, and the use of topical or systemic anti-mite drugs. Understanding the significance of Demodex mites in ocular diseases is crucial for accurate diagnosis and the formulation of appropriate management strategies. In recent years, there has been a growing body of research on Demodex mite. It is necessary to update the diagnositic and therapeutic techniques for ocular surface diseases associated with Demodex mite infection. Therefore, this paper reviews the etiology, epidemiology, pathogenic mechanism, and detection methods of Demodex mite. It also discusses the relationship between Demodex mite infection and various ocular surface diseases, as well as the corresponding treatment methods, with the aim of providing a reference for the research on ocular surface diseases related to Demodex mite infections.
