A Previously Healthy 22-Year-Old Man Comes to the Physician Because

A previously healthy 22-year-old man comes to the physician because of a 1-week history of fever, fatigue, myalgia, sore throat, and difficulty swallowing. He works as a tour guide but has been unable to go to work for the last few days because he is easily exhausted. He has no history of serious illness and takes no medications. He appears lethargic. His temperature is 38.7°C (101.7°F) , pulse is 72/min, and blood pressure is 116/74 mm Hg. Examination of the neck and oropharynx shows tender cervical lymphadenopathy and erythematous, swollen tonsils with white exudates. Lungs are clear to auscultation. The liver is palpated 3 cm below the right costal margin and the spleen is palpated 2 cm below the left costal margin. His hemoglobin concentration is 13.2 g/dL and his leukocyte count is 16,400/mm3. A blood smear shows atypical lymphocytosis. A heterophile antibody test is positive. Which of the following is most likely to be elicited on further history?

A) Anal sexual intercourse
B) Contact with saliva
C) Exposure to urine
D) Prior blood transfusion
E) Recent tick bite
F) School trip to South Asia