A 40 year-old accountant presents for advice on measles prevention. He reports disembarking from an airplane approximately 40 hours ago, and now being notified that one of the passengers on the plane has been diagnosed with measles today. He denies any chronic health problems, states he received “all the shots I should have” when he was a child. However, he is unable to produce documentation of childhood vaccinations. Which of the following represents the most appropriate action? ...