Cause and symptoms

Scabies is a skin infestation caused by a very tiny mite known as the Sarcoptes scabiei. These microscopic mites can live on your skin for up to two months. After mating on the skin surface, the female mite digs tunnels in the cuticle of the skin and lays eggs in the burrows. After 3-10 days, the larvae hatch, move on the skin, become pupae, and then become adults, which can survive on human skin for 2-4 weeks. The digging activity of the female mite and the presence of mite eggs in the subcutaneous burrows cause skin symptoms similar to allergic reactions, in addition to unbearable itching. Because the mites like to be active at night, the itching is especially severe at night, which can make the patient irritable and cause difficulties sleeping. This itching makes the patient scratch uncontrollably, which causes scabies to spread to other places along with the itching, and finally spreads all over the body. The representative characteristic tunnels and cavities of scabies are very small and are often covered by scratches, but the resulting papules are very obvious, so scabies is often misdiagnosed as pruritus or eczema.

Scabies is infected through close contact with the human body, mattresses, animals such as cats and dogs with scabies mites, so after one person in the family suffers from scabies, it is easy to spread at home. There are no symptoms at the initial stage of post-infectious scabies, and the onset usually begins four to six weeks later. Therefore, the patient needs to trace back who had close contact with at least one month before the onset of symptoms, such as sleeping on the same bed. Bed, interdressing, sexual relations, etc., because these activities can easily cause infection. However, if a person who has suffered from scabies is re-infected, there is no incubation period and the onset of scabies will be rapid. Because scabies is highly contagious and has a long incubation period, patients must receive treatment immediately, and people who have had close contact (not necessarily sexual contact) should receive treatment at the same time.