Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Crusted scabies ?
    ### Response:
    Crusted scabies (also called Norwegian scabies) is a severe form of scabies that most often occurs in people who have a weakened immune system, neurological disease, the elderly, the disabled, or those who are mentally incapacitated. It is characterized by thick crusts of skin that contain large numbers of scabies mites and eggs.
    