During an influenza epidemic, a 6 year-old child is seen with fever and a severe sore throat.
A throat swab is taken for culture and the child is sent home. The next day, he is reported to have persistent vomiting and increased lethargy. On examination, he is delirious and disoriented. No rash is noted. His reflexes are hyperactive. The liver edge is 3 cm below the right costal margin in the midclavicular line. Which of the following is the most likely diagnosis?
A. acute bacterial meningitis
B. Guillain Barré syndrome
C. Reye syndrome
D. measles encephalitis