Who can get it?

Roseola is rarely seen in adults, since contraction of the disease as an infant results in lifelong immunity.

Roseola is most common in children between 6 months and three years of age.

Repeat attacks are known to occur, but are rare.

Roseola can be found all over the world, as it is a common virus and 90% of children contract it by 2 years old.

http://www.nlm.nih.gov/medlineplus/ency/article/000968.htm