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Scrub Typhus

(Tsutsugamushi Disease; Mite-Borne Typhus; Tropical Typhus)


William A. Petri, Jr

, MD, PhD, University of Virginia School of Medicine

Reviewed/Revised Jan 2024
Topic Resources
  • People with scrub typhus have a fever, chills, and a headache, followed by a rash several days later.

  • To diagnose the infection, doctors test a sample of the rash and sometimes do blood tests.

  • Scrub typhus is treated with an antibiotic.

Scrub typhus occurs in Japan, Korea, China, India, and northern Australia. The disease is transmitted to people when they are bitten by a chigger (mite larva).

Symptoms of Scrub Typhus

Symptoms of scrub typhus begin suddenly, about 6 to 21 days after the bacteria enter the body. They include fever, chills, a headache, and swollen lymph nodes. A black scab may develop at the site of the chigger bite. People may have a cough during the first week of fever. A rash appears about 5 to 8 days after the fever starts.

Diagnosis of Scrub Typhus

  • A doctor's evaluation

  • Biopsy and testing of the rash

  • Blood tests

The diagnosis of scrub typhus is suggested by symptoms in people who have recently been to an area where scrub typhus is common (such as Central Asia, southeast Asia, South Asia, and northern Australia) and have participated in outdoor activities, such as camping or visiting farms, which could expose them to chigger bites.

To confirm the diagnosis, doctors may do an immunofluorescence assay, which uses a sample from the rash (biopsy). Or they may use the polymerase chain reaction (PCR) technique to enable them to detect the bacteria more rapidly.

Doctors may do blood tests that detect antibodies to the bacteria. However, doing the test once is not enough. The test must be repeated 1 to 3 weeks later to check for an increase in the antibody level. Thus, these tests do not help doctors diagnose the infection immediately after someone becomes ill but can help confirm the diagnosis later.

Treatment of Scrub Typhus

  • An antibiotic

Treatment of scrub typhus usually consists of doxycycline (a type of antibiotic called a tetracycline), taken by mouth, People take this antibiotic until they improve and have had no fever for 48 hours, but they must take it for at least 7 days. With treatment, people recover quickly.

Although some tetracyclines taken for longer than 10 days can cause tooth staining in children younger than 8 years old, short courses (5 to 10 days) of doxycycline in children of all ages is recommended by the American Academy of Pediatrics and other experts and can be used without causing tooth staining or weakening of tooth enamel (see also Centers for Disease Control and Prevention (CDC): Research on doxycycline and tooth staining).

Prevention of Scrub Typhus

Prevention involves clearing brush and spraying infested areas with insecticides to eliminate or decrease the mite population.

If people are likely to come in contact with the chiggers, they should use insect repellents such as DEET (diethyltoluamide).

Drugs Mentioned In This Article

Generic Name Select Brand Names
Acticlate, Adoxa, Adoxa Pak, Avidoxy, Doryx, Doxal, Doxy 100, LYMEPAK, Mondoxyne NL, Monodox, Morgidox 1x, Morgidox 2x , Okebo, Oracea, Oraxyl, Periostat, TARGADOX, Vibramycin, Vibra-Tabs
Emtet-500, Panmycin, Sumycin
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