Epidemic Typhus

After an incubation period of 7 to 14 days, fever, headache, and prostration suddenly occur. Temperature reaches 40° C in several days and remains high, with slight morning remission, for about 2 weeks. Headache is generalized and intense. Small, pink macules, which appear on the 4th to 6th day, rapidly cover the body, usually in the axillae and on the upper trunk and not on the palms, soles, and face. Later, the rash becomes dark and maculopapular. In severe cases, the rash becomes petechial and hemorrhagic.

Splenomegaly sometimes occurs. Hypotension occurs in most seriously ill patients. Vascular collapse, renal insufficiency, encephalitic signs, ecchymosis with gangrene, and pneumonia are poor prognostic signs.

Brill-Zinsser disease, a mild recrudescence of epidemic typhus, can occur years after the initial infection if host defenses falter.

Louse infestation is usually obvious and strongly suggests typhus if history (eg, living in or visiting an endemic area) suggests possible exposure.

For details, see Diagnosis of Rickettsial and Related Infections Diagnosis Rickettsial diseases (rickettsioses) and related diseases (anaplasmosis, ehrlichiosis, Q fever, scrub typhus) are caused by a group of gram-negative, obligately intracellular coccobacilli. All... read more .

Primary treatment of epidemic typhus is doxycycline 200 mg orally once followed by 100 mg twice a day in adults until the patient improves, has been afebrile for 24 to 48 hours, and has received treatment for at least 7 days.

Although some tetracyclines can cause tooth staining in children < 8 years of age, the Centers for Disease Control and Prevention (CDC) advises that a course of doxycycline 2.2 mg/kg orally or IV twice a day is warranted (1 Treatment references Epidemic typhus is caused by Rickettsia prowazekii. Symptoms are prolonged high fever, intractable headache, and a maculopapular rash. (See also Overview of Rickettsial and Related Infections... read more ). Research indicates that short courses of doxycycline (5 to 10 days, as used for rickettsial disease) can be used in children without causing tooth staining or weakening of tooth enamel (2 Treatment references Epidemic typhus is caused by Rickettsia prowazekii. Symptoms are prolonged high fever, intractable headache, and a maculopapular rash. (See also Overview of Rickettsial and Related Infections... read more ).

Chloramphenicol 500 mg orally or IV 4 times a day for 7 days is 2nd-line treatment. Oral chloramphenicol is not available in the US, and its use can cause adverse hematologic effects, which requires monitoring of blood indices.

Severely ill patients with epidemic typhus may have a marked increase in capillary permeability in later stages; thus, IV fluids should be given cautiously to maintain blood pressure while avoiding worsening pulmonary and cerebral edema.

Immunization and louse control are highly effective for prevention. However, vaccines are no longer available. Lice may be eliminated by dusting infested people with malathion or lindane. Bedding and clothing should be washed at least once a week in hot water (> 54 C) and dried on high heat. Non-washable clothing and items can be dry-cleaned or sealed in a plastic bag and stored for 2 weeks. Bedding and clothing also can be treated with the insecticide permethrin.