Relapsing fever is a bacterial infection caused by the spiral-shaped Borrelia species (excluding Borrelia burgdorferi, the causative organism of Lyme disease) transmitted by lice or tick bites.
-it occurs in two forms linked to the mode of transmission and the Borrelia species involved
Louse-borne relapsing fever (LBRF): epidemic; caused by Borrelia recurrentis, transmitted by the body louse
Tick-borne relapsing fever (TBRF): endemic; caused by multiple Borrelia species, transmitted by ticks
Symptoms & Signs
After a louse or tick bite, Borrelia enters the body, multiplies and produces endotoxins which affect the liver, spleen, and capillaries.
-Abrupt onset of fever, chills, nausea, vomiting, arthralgia, headaches
rashes, hepatomegaly, splenomegaly
-Delirium, neurologic and psychological abnormalities
-Attacks terminates abruptly after 3-10 days
-Relapse occurs after an interval of 1-2 weeks
-Three to ten relapses may occur before recovery
Thin or thick blood smears stained with Wright or Giemsa stain reveal large, loosely coiled spirochetes; PCR techniques, serology
Procaine Penicillin G, tetracyclines, erythromycin