Most of the rashes that appear after the fever subsides are caused by the emergency rash of young children, which mainly manifests itself as a rash that appears all over the body after a sudden drop in body temperature, most early in the neck and trunk, then spreading to the whole body, more often in the waist and buttocks, followed by the forehead, neck, upper limbs and other parts, and less often in the face, elbows and below the knees. The rash is a congested rose-colored papule, about 2-3mm in diameter, usually appearing within 24 hours after the fever subsides, and fading completely within 1-2 days, with no flaking or pigmentation after the rash subsides. During the entire period of illness, the baby is in good spirits, except for fever.