Measles in a Patient with Presumed Immunity - Los Angeles County, 2015

On February 14, 2015, patient A, aged 17 years, was seen in an emergency department for evaluation of reactive airway disease. In the waiting room at the same time were two siblings, aged 6 months, presenting with fever and rash; these two children (patients B and C) were later confirmed to have measles. Patient A began a 5-day course of oral prednisone (50 mg per day); however, symptoms continued, and patient A returned to the emergency department the next day and received 125 mg of intravenous (IV) methylprednisolone. Patient A had documentation of receipt of 2 doses of measles, mumps, and rubella (MMR) vaccine at ages 12 months and 4 years.