Causes of children’s low fever for three days, mainly including the following situations: 1, due to children suffering from acute upper respiratory tract infection caused by the symptoms. Children with acute upper respiratory tract infection, if the symptoms of the infection is not very serious, just have a low fever, children will also have nasal congestion, runny nose, sore throat and other accompanying symptoms, is due to the toxicity of the infection of the pathogenic bacteria is relatively weak caused by the children’s white blood cell level count is not very high. 2, due to the children suffering from indigestion caused by the symptoms. After suffering from dyspepsia, it can also lead to a fever of accumulation of food, and children at this time also have a low fever.3. If children suffer from rubella, it can also lead to a low fever, accompanied by swollen lymph nodes in the occipital area and behind the ears, and small red rashes all over the body and other symptoms.