Children with a fever of 39 degrees, may be caused by upper respiratory tract infection, gastroenteritis, etc., can blow the air conditioning, but need to pay attention to the temperature settings and so on. Children with a fever of 39 degrees Celsius, the need for timely fever reduction, to avoid high fever induced convulsions, including physical fever and drug antipyretic. The use of air conditioning to control the ambient temperature is one of the effective physical cooling methods, keep the indoor temperature at about 24-26 ° C, reduce the child’s clothing appropriately, can help the child to dissipate the heat, the use of air conditioning to avoid the temperature is too low, the direct front to use, otherwise it may induce chills. In addition, has exceeded 38.5 ° C, purely physical antipyretic effect may be slow, you can at the same time under the guidance of the doctor to use ibuprofen or acetaminophen medication to reduce fever, but also need to be timely supplementation of water, to avoid dehydration caused by fever. There are many reasons for children to have fever, if repeated fever, accompanied by coughing, coughing up phlegm, mental depression, etc. need to consult a doctor in a timely manner.