Rash after MMR fever is not a pediatric emergency rash. 1. MMR: generally refers to the MMR vaccine, mainly able to prevent measles, mumps and rubella, after vaccination there may be adverse reactions, the more common is fever, there will be a rash, but this rash is not contagious, and after a period of time can be relieved naturally, and does not belong to the pediatric emergency rash. 2. Pediatric emergency rash: generally refers to the early childhood emergency rash, this is a rash disease, most of them are caused by herpesvirus 6 and herpesvirus 7 infections, after infection with this virus, the beginning of the symptoms is fever, usually high fever, body temperature is often higher than 39 ℃, sometimes can be as high as 40 ℃, the fever lasts for 3~5 days, after the fever will subside, and then appear the skin rash. To sum up, the rash after MMR fever is not the same as pediatric emergency rash, it is two different situations, you should consult a doctor in time, make a clear diagnosis and deal with it.