Air conditioning is generally not recommended if you develop a fever after the MMR vaccine. Fever after MMR vaccination may be caused by an adverse reaction to the vaccine, or it may be caused by exposure to cold or infection. Regardless of the cause of fever after MMR vaccination, it is important to avoid exposure to cold and wind. Air-conditioning should be minimized during this period to prevent exacerbation of the fever and other discomforts. Low fever can be physically cooled down by wiping the forehead with warm water, if the temperature is higher than 38.5 ℃, you can take oral antipyretic medication under the guidance of a physician, and the fever will usually disappear in about three days. In addition, it is also necessary to do a good job of cleaning the injection site, avoid touching the injection site directly with your hands, in order to prevent infection. If the fever persists for more than 24 hours after the injection of MMR vaccine, or the fever is more serious, with a high fever higher than 39 degrees or change of consciousness, it is necessary to go to the hospital for examination in time, to clarify the cause of the disease and timely treatment.