The term “pediatric rash” is correctly called “infantile rash”, which is an acute infectious disease caused by a virus that can be transmitted to other children. It is an acute infectious disease mainly caused by human herpesvirus types 6 and 7, which can be spread by saliva from the respiratory tract. The incubation period for toddler emergency rash is 1 to 2 weeks, during which time it should be closely observed, and if a high fever develops, it should be isolated so that it is not transmitted to other children. Typical symptoms of toddler emergency rash are a sudden high fever that lasts for 3 to 5 days, followed by a sudden drop in temperature and the appearance of a red maculopapular rash all over the body, which will subside on its own after 2 to 3 days. Most children have had the disease before the age of 2 years. The prognosis of the disease is good in the absence of serious complications, but parents should be aware of the need to prevent the occurrence and spread of the disease.