Scabies (lat. Sarcoptes scabiei var. hominis) is a skin parasite which belongs to the family of ich mites (lat. Sarcoptidae) and causes itch. It affects 200 to 300 million people a year.

How does it spread?

The cause of infestation is physical contact with an infected person or contaminated objects such as bed sheet, clothes, mattress or even some hard objects. Scabies mostly spread in kindergartens, schools and old-age homes. Healthcare workers are one of the most affected groups. Socio-economic status and hygienic habits of an individual do not play the role in infestation with this parasite. Anyone can be affected.

Reproduction cycle

The size of this self-effacing parasite is around 0.35 millimetres. They are visible only under microscope after skin swab and they can sometimes be visible to the naked eye as a black dot. Scabies nourish on skin remnants, so they infest the outer layer of the skin in which they dig tunnels where they lay eggs. Females lays 2 or 3 eggs a day and after 24-48 hours maggots are hatched. Those maggots turn into adults after 10-14 days after which the new cycle begins. Males live on top of the skin and thy migrate into the tunnels only for propagation and food. And individual scabies can live up to two days outside the host in ideals temperature conditions, which is 21$ and 40-80% of moisture in the air.

Dermatitis or itch?

One of the most significant symptoms of scabies, or so-called mange, is an intense itch of the whole body which is an alergic reaction to faeces and eggs. It appears 3-4 weeks after exposure to the source of infection. Many patients have noticed an increased itching during the night or after hot shower because of the warmer skin. Expect for the caracteristic itching, red pustules and lines, which represent the tunels that parazites dug under the skin, may appear on the body. The symptoms of itch are similar to the symptoms of other skin diseases such as dermatitis. Because of this, scabies can only be diagnosed with a skin swab.

Therapy

Scabies should be treated because there is a chance of staphylococcus or streptococcus bacterial infections. Patients are prescribed topical 5% Permetrin or 25% benzyl benzoate which both have scabicidal effect – attack on parazite’s nervous system. For more severe infestations, patients are prescribed oral therapy with Ivermectin which was especially popular during the year of 2020. because of the COVID-19 virus. During the therapy time, it is essential to wash all the clothes which were in contact with an infested person.

In the end

Scabies is an uncomofrtable skin disease with symptoms similar to dermatitis symptoms. The parasite is small and easily transmitted. In order to reduce the suspicion of infestation – it is best to have a dermatological examination.

LIterature

Chandler D, J, Fuller L, C: A Review of Scabies: An Infestation More than Skin Deep. Dermatology 2019;235:79-90. Richards RN. Scabies: Diagnostic and Therapeutic Update. J Cutan Med Surg. 2021 Jan-Feb;25(1):95-101

Photo source

https://www.freepik.com/free-photo/young-woman-scratching-her-neck-due-itching-gray-background-female-has-itching-neck-concept-allergy-symptoms-healthcare_28092410.htm#query=itch&position=4&from_view=search&track=sph