A 5-year-old boy was brought to the emergency department by his parents to evaluate a rash. He initially had a fever and runny nose for one week. After the fever subsided, a rash began to appear on his face. It looks particularly red over his cheeks. He does not have a history of sore throat and cough. His immunizations are up to date. A few days ago, he went hiking with his school friends but had not traveled outside the country. Temperature is 37.8 C (99 F), blood pressure is 90/60 mm of Hg, and pulse is 101/min. On physical examination, the patient is irritable, and an erythematous rash is present over his cheeks. An image of the rash is shown in the exhibit.