The rash usually develops just as the fever resolves. It is common in children ages 3 months to 4 years and most common in infants 6 to 12 months. Older children and adults can also get roseola ...

In roseola, after an incubation period of 5–15 days, infected children develop high fevers that last 3–5 days. This is followed by the acute onset of a rosey pink, nonpruritic macular rash ...