Acute rash in babies is usually caused by herpes virus infection, and the typical symptoms are fever, skin rash and other symptoms. 1. Fever: after the appearance of acute rash, baby’s body temperature usually increases, and the temperature may exceed 39 degrees, and in severe cases, convulsions may occur, and after 3~5 days, the body temperature may decrease gradually. 2. Rash: After the fever subsides, red papules usually appear on the local skin, usually on the chest, back and neck first, and then spread to the face or limbs. Inadequate treatment may lead to many serious complications, such as seizures, encephalitis, aseptic meningitis and so on. 3. Other Symptoms: After the baby develops emergency rash, there may be symptoms related to the respiratory system and the digestive system, such as mild cough, runny nose, diarrhea, vomiting, abdominal pain and so on. Parents should take their babies to the doctor for examination and treatment to avoid serious complications.