The most common cause of unexplained fever in small children is the development of acute infantile rash. In the early stages of fever, there are no signs other than an increase in body temperature, but a hematological examination often reveals traces. At this time there is often a mild elevation of eosinophils in the blood count, often accompanied by an elevation of C-reactive protein, indicating a viral infection. Small children can be treated with antiviral medications, such as Four Seasons Antiviral Combination, Pu Di Lan Anti-inflammatory Oral Liquid, Blue Scutellaria Oral Liquid, or Ribavirin Granules, all of which are effective. The temperature of the fever is often high, in many cases over 39 degrees, or even 40 degrees, so it is necessary to reduce the fever, you can give children oral ibuprofen suspension, or acetaminophen granules to reduce the fever treatment. Often after 3-5 days of fever, there is a sudden drop in temperature, followed by the appearance of a rash. Don’t be alarmed when the rash appears, as long as there are no serious complications, the rash will dissipate on its own in 2-3 days.