If your baby has a fever of unknown origin, treat the fever first by taking the temperature immediately. If the fever is high, give your child fever-reducing medication such as ibuprofen or acetaminophen in a timely manner. If the fever is low, generally good, no other clinical symptoms, pay attention to give the child appropriate more water, you can also give the child a cooling patch, a warm bath, etc., for physical cooling, perhaps the child’s fever will go down, the disease will be well. If the child has recurrent fever or poor spirit, accompanied by obvious clinical symptoms of other systems, such as cough, shortness of breath, diarrhea, abdominal distension, etc., take the baby to the pediatric emergency room as soon as possible. After a detailed physical examination by the doctor, it is usually necessary to do blood routine, C-reactive protein, calcitoninogen and other tests to understand the status of the infection and treat it according to the etiology of the infection.