a zoonosis of protean manifestations
spectrum of symptoms is extremely broad
vast majority asymptomatic or mild
febrile illness of sudden onset.
Other: chills, headache, myalgia, abdominal pain, conjunctival suffusion, and less often a skin rash.
if present, rash is often transient, lasting less than 24/24. This anicteric syndrome usually lasts ~1/52, and resolution coincides with the appearance of antibodies.
The fever may be biphasic and may recur after a remission of 3 to 4 days.
headache is often severe, with retro-orbital pain and photophobia.
Myalgia affecting the lower back, thighs, and calves is often intense
