(See also Overview of Rickettsial and Related Infections Overview of Rickettsial and Related Infections 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 
.)
Murine typhus is a rickettsial disease.
Animal reservoirs include cats, wild opossums, rats, mice, and other rodents. Rat fleas and probably cat fleas and opossum fleas transmit organisms to humans through bites. Fleas are also natural reservoirs for R. typhi; infected female fleas can transmit organisms to their progeny. Distribution is sporadic but worldwide; the incidence is low but higher in rat-infested areas.
Symptoms and Signs of Murine Typhus
After an incubation of 6 to 18 days (mean 10 days), a shaking chill accompanies headache and fever in patients with murine typhus. The fever lasts about 12 days; then temperature gradually returns to normal.
The rash and other manifestations are similar to those of epidemic typhus but are much less severe. The early rash is sparse and discrete.
Mortality is low but is higher in older patients.
Diagnosis of Murine Typhus
Clinical features
Biopsy of rash with fluorescent antibody staining to detect organisms
Acute and convalescent serologic testing (serologic testing not useful acutely)
Polymerase chain reaction (PCR)
Treatment of Murine Typhus
Doxycycline
Primary treatment is doxycycline 200 mg orally once followed by 100 mg twice a day in adults until the patient improves, has been afebrile for 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 Murine typhus is caused by Rickettsia typhi and R. felis, which are transmitted to humans by fleas; it is clinically similar to but milder than epidemic typhus, causing chills... 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 Murine typhus is caused by Rickettsia typhi and R. felis, which are transmitted to humans by fleas; it is clinically similar to but milder than epidemic typhus, causing chills... read more ).
For details of treatment, see Treatment of Rickettsial and Related Infections Treatment 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 .
Treatment references
1. Centers for Disease Control and Prevention: Information for Healthcare Providers, Typhus Fevers
2. Todd SR, Dahlgren FS, Traeger MS, et al: No visible dental staining in children treated with doxycycline for suspected Rocky Mountain Spotted Fever. J Pediatr 166(5):1246-51, 2015. doi: 10.1016/j.jpeds.2015.02.015. Epub 2015 Mar 17. PMID: 25794784.
Prevention of Murine Typhus
Incidence of murine typhus has been decreased by reducing rat and rat flea populations. No effective vaccine exists.
Key Points
Murine typhus is transmitted to humans by fleas.
Symptoms begin with a shaking chill, headache, and fever; the rash and other manifestations are similar to those of epidemic typhus but are much less severe.
Treat with doxycycline.
Drugs Mentioned In This Article
| Drug Name | Select Trade |
|---|---|
doxycycline |
VIBRAMYCIN |
