A child’s fever once a month is often due to low immunity, which can easily lead to pathogenic infections, which may be caused by colds, tonsillitis, pneumonia, etc., or non-infectious diseases. 1. Colds: the most common type of acute upper respiratory tract infectious diseases, mostly due to viral infections, such as rhinovirus, parainfluenza virus, coronavirus, coxsackievirus, etc., but also may be secondary to bacterial infections, which can easily cause fever, cough, runny nose and other symptoms. 2. Tonsillitis: It may be acute tonsillitis or acute attack of chronic tonsillitis, which often causes fever, sore throat and other symptoms. 3. Pneumonia: it is a kind of inflammation of pediatric lungs caused by bacterial or viral infection and other pathogens, and the main symptoms caused by it are fever, shortness of breath, coughing, and dyspnea. 4. Non-infectious diseases: rheumatoid arthritis, for example, can appear repeatedly fever, accompanied by joint swelling and other symptoms. Children with fever once a month, try to be able to go to the hospital to identify the cause, usually also let the child more exercise, diet to increase nutrition, improve immunity.