Scabies is an infection caused by a parasite called the mite (scabies).The Hizen mite is a type of mite, and it is very small, about 0.2-0.4 mm in length, so it can hardly be seen with the naked eye.
Symptoms are severe itchiness, lumps, and linear rashes appear from the neck down to the entire body. There is strong itchiness at night. Occur after the incubation period of about 4 weeks after infection.
The sarcoptes scabie mate on the skin, and the female digs a tunnel into the stratum corneum of the skin to lay 10-25 eggs.This is called the "scabies tunnel", and it turns into a curved, linear, earthworm-swollen rash. Inside the tunnel there are eggs and dung, and at the tip of the tunnel there is a female sarcoptes scabie.When the egg hatches in 3-7 days, it comes out on the skin and becomes an adult in 2-3 days.
Severe itching, a symptom of scabies, is an allergic reaction to dung and molted shells of the sarcoptes scabie.
In scabies, there are "normal scabies" where the parasitism of sarcoptes scabie is less than a few dozen, and "keratinized scabies" where the skin becomes hard by parasitism of as many as 100 million to 200 million sarcoptes scabie. Keratinized scabies is usually less itchy than scabies, but it is characterized as highly infectious.

Route of infection and prevention

You can be infected by direct contact with the skin. Sexual activity is an intimate skin contact and carries a high risk of infection. You can also get infected by sharing clothes, bedding, towels, co-sleeping or huddling.
However, regardless of age or health status, there is a risk of infection if theres a direct contact with the skin of a person suffering from scabies. In particular, keratosis scabies is highly contagious, so extra caution is necessary.
If you had contact with a person with scabies, wash your hands thoroughly and avoid skin contact for a long period. Avoid sleeping in the same room, avoid sharing clothing, bedding, and towels.
If your sexual partner is diagnosed with scabies, see a dermatologist for consulation.

Testing

Diagnosis is done through examination of the sample tissue from the area of the scabies tunnel using a microscope. Presense of adult scabies, molted shells or dung are usually found in the skin surface.
A dermoscopy is used to illuminate the surface of the skin, where a female mite is found at the tip of the scabies tunnel.
However, in the case of scabies, there is usually a small number of parasitic mites, so repeated tests may be performed.

Treatment

Topical and oral medication is used for treatment of scabies. It is important to apply the topical medication to the entire body part and not just limit to where the symptom appears. Use of anti-itch cream may also be used.
You may exterminate the sarcoptes scabie remaining in clothes, bedding, towels, etc. with an insecticide or by washing them.
If treatment and extermination is not done together, it is hard to reach the maximum effect of the treatment.
The treatment is complete once the adult mites and eggs are exterminated, and symptoms such as itching are gone, but reinfection is possible if theres direct skin contact with a person with scabies.
If left untreated, it will only get worse and will never heal naturally.