Below is an instruction from Human. Write a response.
    ### Instruction:
    How to diagnose Parasites - Lice - Head Lice ?
    ### Response:
    Misdiagnosis of head lice infestation is common. The diagnosis of head lice infestation is best made by finding a live nymph or adult louse on the scalp or hair of a person.
    
Because adult and nymph lice are very small, move quickly, and avoid light, they may be difficult to find.
    