A 7-year-old boy was brought to the doctor by his mother with a rash of scaly papules primarily on his trunk, some of which had crusted or healed. A few of the lesions were hemorrhagic. They had appeared just a few days ago and the little boy complained they were very itchy. His mother initially thought it was a mild case of chicken pox because he also had a fever, but she also knew he had been vaccinated. During the exam, the doctor detected generalized lymphadenopathy.