Incubation period: often 5-14 days with range of 2-30 days
Clinical findings in mild disease:
(1) febrile illness with sudden onset, sometimes with a biphasic pattern (afebrile for 3 or 4 days)
(2) moderate to severe headache with retro-orbital pain and photophobia
(3) muscle pain and tenderness, often involving the lower back, thighs and/or lower legs
(4) aseptic meningitis
(5) petechial or purpuric rash
(6) conjunctival suffusion (reddish from blood)
(7) chills
(8) abdominal pain with tenderness of the abdominal wall
(9) dehydration
(10) vomiting
(11) epistaxis or mild bleeding
(12) sore throat and dry cough
