II. Epidemiology

  1. Typhus is rare worldwide

III. Pathophysiology

  1. Vector-borne illnesses caused by Rickettsial or Oriential infection

IV. Types

  1. Typhus or Epidemic Typhus
    1. Louse-borne transmission of Rickettsia prowazekii
    2. Typically occurs during war or over-crowded conditions, transmitted by Body Lice
    3. May recur years after initial infection (Brill-Zinsser Disease)
  2. Murine Typhus or Endemic Typhus
    1. Flea-borne transmission from rats (or mice, cats)
    2. Vectors include rat flea (Xenopsylla) and squirrel flea (Orchospea)
  3. Scrub Typhus
    1. Mite-borne transmission of Orienta tsutsugamushi
    2. Vector: Larval mite Chigger (Leptotrombidium)
    3. Seen in Southeast Asia

V. Findings

  1. Typhus or Epidemic Typhus
    1. Presents with abrupt onset fever and intractable Headache
    2. Nonproductive cough may also be present
    3. Rash is a late sign, seen in two-thirds of patients, starting on trunk and spreading to extremities
  2. Murine Typhus or Endemic Typhus
    1. Presents with fever, Headache and myalgias
    2. Maculopapular Rash in half of patients
    3. Thrombocytopenia in 48% of patients
  3. Scrub Typhus
    1. Presents with fever, Headache, malaise and myalgias
    2. Tinnitus and Hearing Loss (or Deafness) may occur
    3. Regional Lymphadenopathy may be present
    4. Macular rash in 50% of patients (may be associated with eschar)
    5. Thrombocytopenia in most patients

VI. Management

  1. Typhus or Epidemic Typhus
    1. Eliminate vector (e.g. kill lice)
    2. Doxycycline 100 mg twice daily for 5 days (or 200 mg once) OR
    3. Chloramphenicol 500 mg oral or IV four times daily for 5 days
  2. Murine Typhus or Endemic Typhus
    1. Spontaneously resolves without treatment in 14 days
    2. Doxycycline 100 mg twice daily for 7 days OR
    3. Chloramphenicol 500 mg oral or IV four times daily for 7 days
  3. Scrub Typhus
    1. Doxycycline 100 mg twice daily for 7 days (if resistance suspected, add Rifampin) OR
    2. Chloramphenicol 500 mg oral or IV four times daily for 7 days OR
    3. Azithromycin 500 mg oral or IV for 1 dose (if resistance suspected, extend for 3 days)

VIII. References

  1. Sexton in Calderwood (2016) Epidemic Typhus, UpToDate, IOS app accessed 4/14/2016
  2. (2016) Sanford Guide to Antibiotics, IOS app accessed 4/14/2016
  3. Huntington (2016) Am Fam Physician 94(7): 551-7 [PubMed]

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