If a baby develops a rash while having a fever, it is likely that he or she has a rash, and it is best to go to the hospital to have a doctor look at what type of rash is present for targeted treatment. Most rash illnesses are caused by viral infections, and blood tests and C-reactive protein can often reveal abnormalities. For example, C-reactive protein is usually normal and white blood cells are often reduced or normal, with lymphocytes predominating. The baby can be treated with antiviral drugs, such as oral ribavirin granules, Pudilan anti-inflammatory oral solution, and Four Seasons antiviral combination. If the itchiness is accompanied by the bun, you can give the child a localized application of glyburide lotion, which can effectively stop the itch. For fever, if the temperature is high, more than 38.5 ℃, you can take oral antipyretics.