A 28-year-old woman presents with a 5-day history of progressive jaundice, vomiting, nausea, and malaise. She has developed a fever and has a 2-day history of dark urine. She has no history of intravenous drug use and has had no recent transfusions; she denies any sexual contact in the last 3 months. The patient has recently returned from a trip to Mexico where she consumed various foods from street vendors. Physical examination reveals a jaundiced patient. An abdominal examination is significant for a palpable liver edge 2 cm below the right costal margin and a total liver span of 12 cm below the mid-clavicular line. Blood is drawn for cultures, a complete blood cell count, and liver function tests. Blood studies are significant for a direct bilirubin of 13.0 mg/dL, aspartate aminotransferase of 1,800 U/liter, and alanine aminotransferase of 2,500 U/liter. Blood cultures are negative and serological studies are conclusively diagnostic. What is the most probable cause of the patient's symptoms?
A) Hepatitis A
B) Norwalk virus
C) Rotavirus
D) Adenovirus
E) Parvovirus
