Scabies is an infectious disease that occurs worldwide. It spreads rapidly where people live together in close quarters(families, old people's homes, schools, nurseries). Scabies is particularly common in areas with low hygiene standards. The incidence is between 1 and 30 percent, depending on the environment.
Infection with scabies occurs through close physical contact, especially during sexual intercourse. This is why scabies is a sexually transmitted disease (STD). According to the Infection Protection Act, scabies must be reported if people in communal facilities such as schools or nurseries fall ill.
The causative agent of scabies is a parasite called Sarcoptes scabiei. It belongs to the arachnid family and is about 0.2 to 0.4 millimeters in size. It has a translucent body and eight legs arranged in pairs. It also has a strong jaw.
The female itch mite nests in the skin, where it feeds and lays 1-3 eggs a day. A few days later, larvae hatch from them, which in turn develop into sexually mature itch mites within two to three weeks. They continue to reproduce rapidly.
The scabies mite Sarcoptes scabiei causes scabies @ Aliaksei /AdobeStock
In most cases, scabies is transmitted through close physical contact with infected people. Infection is therefore mainly possible during sexual intercourse.
Sharing bed linen, mattresses, blankets, pillows, towels or clothing can also result in infection.
Other possible sources of infection are soft toys, thermometers and blood pressure cuffs.
The risk of infection is greatest in places where there is a lack of hygiene or where people live together in confined spaces. Examples include old people's homes, homeless shelters, nurseries and schools.
After the initial infection with scabies, two to six weeks pass before the first symptoms appear.
Symptoms include an itchy rash and large, inflammatory skin lesions.
If a person then becomes infected with scabies again, the first symptoms appear after just a few days.
The scabies mites prefer to infest areas of the body with a thin layer of skin and a high temperature.
These include in particular
- The spaces between the fingers
- The wrists
- The elbows
- The crook of the arm
- The knee
- The chest and armpit area
- The region around the navel
- The buttocks
- The genital region
- The penis
In rare cases, the rash spreads to the arms, thighs, fingers, palms, soles of the feet, stomach or back.
Day 6 after a scabies infection
The typical symptoms of scabies include
- Nodules
- Pustules or papules
- Scaly skin swellings
- Scaly, crusty skin inflammation
- Formation of blisters
Severe itching is also one of the signs of scabies. It is unbearable for those affected , especially at night. Patients scratch themselves more often. This also leads to scratched areas of skin and superficial skin lesions, which in turn are an ideal breeding ground for bacteria. This results in a purulent skin rash.
If a patient suffers from severe itching at night and the characteristic rash, a scabies infection is suspected.
In this case, the patient should consult a specialist in skin and venereal diseases and undergo a thorough examination.
The doctor will first examine the body area with a special magnifying glass for mite ducts and scabies mites.
The mite ducts can be made visible using the ink method. The doctor drops water-soluble ink onto one of the papules. He then takes a sample from the mite ducts or papules with a scalpel or a sharp spoon. He examines the sample under a microscope to see if any clear microscopic pathogens can be detected.
Preferred body areas for mite infestation
Treatment is carried out with an ointment that the patient applies once to the entire body (with the exception of the face). When applied correctly, the cream destroys the scabies mites and prevents re-infection. The skin heals within a few days or weeks.
The product of choice is an ointment containing the active ingredient permethrin, an artificially produced insecticide. Other available remedies are creams or ointments with the active ingredients benzyl benzoate and crotamiton.
It is advisable to prevent re-infection with scabies:
- Treat all people in your close environment. As the first symptoms only appear after a few weeks, you should also include people who do not yet have any symptoms.
- In addition, you should wash bed linen and clothing at 60 degrees Celsius or air them for four days to kill scabies mites, which survive for a maximum of three days without a host.
- Freezing shoes and textiles in the freezer or wrapping them in plastic bags also effectively kills itch mites.
- You should also vacuum beds, armchairs, carpets and floors thoroughly with a vacuum cleaner.
If left untreated, scabies worsens over time and takes a chronic course. Treatment of scabies is therefore essential. Correct treatment leads to a cure in most cases. After the scabies mites have been killed off, itching can persist for several weeks. This is due to the body's allergic reaction to the dead itch mites and the droppings in the skin. It takes some time for the skin changes to heal.
