L.M.
Our pediatrician said the rash stays longer after the disease has healed and in some cases up to 4 weeks. (that does not mean she is contagious)
Calamine lotion, some baking soda in her bath water for any itch or discomfort. Don't rub baby lotion on her as the fragrances used can sometimes aggravate rashes and sensitive skin.
You will have to just grin and bare it until the rash goes away. As long as she does not have a fever or in any pain, she should be just fine.