Rickettsia prowazekii is an obligate intracellular bacteria that causes classic typhus, also known as epidemic typhus. It targets the endothelial cells of small blood vessels. The bacteria is transmitted by the human body louse. Classic symptoms include abrupt onset of fever, headache, rash on the upper chest and axillary area after 5-7 days. Without treatment, mortality can be as high as 10-30%. Treatment involves doxycycline or tetracycline. Relapse can occur years later, known as Brill-Zinsser's disease, with milder symptoms.

1. Rickettsia
prowazekii
Domina Petric, MD

2. Introduction
• Rickettsia prowazekii
causes classic typhus
(typhus exanthematicus,
epidemic typhus).
• This bacteria is obligate
intracellular bacteria,
coccobacill, gram

3. Pathogen Profile Dictionary
http://www.ppdictionary.com/bacteria/bwu
m/prowazekii_files/prowazekii_growing.jpg

4. Patogenesis
Target place for this
bacteria are endotel
cells of all small
blood vessels.

5. Transmission
From louse
(Pediculus humanus
corporis): there is
NO primary lesion or
tache noire, eschara.

6. Clinical presentation
• Incubation period: 1 to 2
weeks (usually 12 days).
•Abrupt onset: fever,
severe headache,
shivering, malaise,
myalgias, arthralgias.

7. Clinical presentation
• After 5 to 7 days from the
first symptoms, purple
macular rash develops
(initially pale on pressure) in
axillary pits and upper part of
the thorax.
• After some time rash

8. Purzuit
http://4.bp.blogspot.com/-
jKd18YbsdD4/Tfe5SY5xmaI/AAAAAAAAHtY/FtNxQIrUa
70/s1600/typhus%2Brash.jpg

9. Clinical presentation
• There is usually NO rash on
hands, feet and face.
• There can be symptoms of
toxemia if the patient is not
treated.
• Mortality of untreated
patients can be from 10% to

10. Clinical presentation
Rare manifestations of the
disease:
• dry cough (with pneumonic
infiltration on chest X ray)
• coma and delirium (CNS
affection)
• myocarditis

11. Treatment

12. Brill-Zinsser´s
disease
• It is late relapse after many
years (10 or more years)
after the primary infection.
• Symptoms are similar to
those of classic typhus,
but milder and shorter in
duration.

13. Literature
• www.ppdictionary.com
• Purzuit.com
• Begovac J. Božinović D.
Lisić M. Baršić B.
Schönwald S. Infectology,
Profil.