Scabies - What Happens
First-time infestation
The first time you are infested with the scabies mite, itching may not begin for several weeks. During this time, you are contagious but may not know that you are carrying scabies mites.
In the first few weeks of scabies infestation, the body develops sensitivity to the mites, their eggs, and their feces. After your body has become sensitized, an allergic reaction is triggered, causing itching. With treatment, the scabies mites die and the itching gradually goes away over a period of days to weeks. Usually a doctor will tell you it is safe for your child to return to school after treatment is completed and the medicine has been washed from the skin. Treatment takes 1 to 3 days depending on the medicine used.
If all of the scabies eggs are not killed by the first treatment, they may hatch and cause symptoms again. Without treatment, the mites reproduce and cause more sores and more itching. Scabies will not go away on its own. Only animal-transmitted scabies will go away without treatment.
Repeat infestation
If you have had scabies and are infested with the mites again, itching will begin almost immediately. The allergic sensitivity developed during the previous exposure triggers an immediate reaction to the mites. Treatment is usually required to kill the mites and eggs. In rare cases, a person's allergic reaction will kill the scabies.
Complications
The most common complication of scabies is a bacterial skin infection, such as impetigo. This most often occurs when the skin has been scratched raw. Hair follicles may also become infected (folliculitis). Antibiotics may be needed to treat a bacterial skin infection.
The skin can become thick, red, and scaly or shiny from persistent scratching.
In rare cases, crusted (Norwegian) scabies, a severe form of scabies, develops. Usually, this type of scabies is most common in people who have weakened immune systems, such as those with HIV. People with crusted scabies may have extreme infestations with tens of thousands of mite. In otherwise healthy people, an infestation is usually limited to about 10 or 15 mites.1
WebMD Medical Reference from Healthwise
