epidemic typhus

see also:

• human louse / lice
• Salmonella typhi (typhoid enteric fever)

• epidemic typhus is caused by Rickettsia prowazekii which is spread by the human body louse

• rare in developed countries
• most cases occur in areas with poor sanitation, crowding, war or natural disasters where body lice infestations are more common
• outbreaks have been reported in parts of Africa, Central and South America, Eastern Europe, and Asia
• cases have occurred in the United States, often linked to contact with flying squirrels

• incubation period 7-14 days
• abrupt onset of high fevers often over 40degC lasting up to 2 weeks
  • severe headache and fatigue with photophobia
  • chills, myalgias
  • nausea, vomiting, cough may occur
• 4-6 days after onset of fever - rash starting on trunk spreading to the limbs but usually sparing the face, palms, and soles
• severe cases may develop confusion and hypotension and may progress to renal failure, encephalitis, myocarditis, pneumonia, vascular collapse, gangrene and death

• skin biopsy / serology / PCR

• early antibiotics - usually doxycycline