Infectious dermatitis is a skin disease caused by infection with pathogenic microorganisms such as bacteria, fungi, viruses, etc. It belongs to a major type of skin disease. 1. Bacterial dermatosis: mainly caused by bacterial infections, such as common folliculitis, boils, dengue, pustular herpes, etc., the causative organisms are mostly Staphylococcus aureus, Streptococcus, etc., which can lead to localized skin pimples, blisters, and pustules with redness, swelling, pain, and so on. 2. Fungal skin disease: mainly is the skin fungus in the human skin parasitism, reproduction and lead to local skin flaking, itching, vesicles and other uncomfortable symptoms of skin diseases. The causative species of fungi are commonly found in ringworm, tinea albicans, red trichophyton and so on. Common diseases include tinea pedis, tinea corporis, tinea cruris, tinea cruris and so on. 3. viral skin disease: mainly for viral infection of the skin, thus leading to skin mucosal lesions of a group of skin diseases, such as common herpes simplex, herpes zoster, human papilloma virus caused by warts, warts caused by the infectious warts virus, hand, foot and mouth disease and so on. Once the above abnormalities appear, you need to go to the hospital in time.