If it shows no signs, it does not have mange! The two main types of mange are sarcoptic and demodectic. Sarcoptic mange causes intense itching, hair loss, red sores, and scaly skin. Demodectic mange does not generally cause itching and is characterized by hair loss in patches, especially around the eyes, head, and legs. In severe demodecosis there can be hair loss all over, thickening of the skin, and itching due to the secondary bacterial infections. Dogs can have the demodex mite without having symptoms, but these dogs do not have mange; the mite merely lives in a benign relationship with the dog and the immune system keeps the mite population under control