Etiology and Epidemiology:-

Epidemic typhus is caused by R. prowazekii and is transmitted by the human body louse. Eastern flying squirrels and their lice and fleas maintain R. prowazekii in a zoonotic cycle.

  • The louse lives in clothing under poor hygienic conditions, particularly in colder climates and classically at times of war or natural disaster.
  • Lice feed on pts with epidemic typhus and then defecate the organism into the bite at their next meal. The pt autoinoculates the organism while scratching.
  • Brill-Zinsser disease is a recrudescent and mild form of epidemic typhus whose occurrence years after acute illness suggests that R. prowazekiiremains dormant in the host.


Epidemic typhus presents abruptly  the onset of high fevers, prostration, severe headache, cough, and severe myalgias. Photophobia with conjunctival injection and eye pain is also common.

  • A rash appears on the upper trunk around the fifth day of illness and spreads to involve all body-surface areas except the face, palms, and soles.
  • Confusion and coma, skin necrosis, and gangrene of the digits are noted in severe cases.
  • Untreated, the disease is fatal in 7–40% of cases. Pts develop renal failure, multiorgan involvement, and prominent neurologic manifestations.


Epidemic typhus is sometimes misdiagnosed as typhoid fever. The diagnosis can be based on serology, immunohistochemistry, or detection of the organism in a louse found on a pt. Cross-adsorption IFA can distinguish  R. prowazekii from R. typhi.


The medicines that can be thought of use are:-

  • Arsenicum
  • Belladonna
  • Carbo veg
  • Eucalyptus
  • Terebinthina.