Scrub Typhus Tsutsugamushi Fever

What is Scrub Typhus?

Scrub typhus (Tsutsugamuchi Fever) is one of three versions of typhus caused by bacteria.  The bacteria that causes scrub typhus is called Orientia tsutsugamushi (previously called a Rickettsia).

The other two forms of typhus are murine typhus and epidemic typhus which are caused by Rickettsia germs.

How do you get Scrub Typhus?

Scrub typhus is transmitted by some types of mites (chiggers) which are found in areas of heavy scrub vegetation. The infection is not transmitted from person to person.

Susceptibility and Resistance

All persons are susceptible, but one attack results in long lasting immunity against any future infections.

Incubation Period

The incubation period for Scrub Typhus is 6-21 days.

What are the Symptoms?

The illness usually begins with the appearance of a characteristic black ulcer where the infected mite was attached.  Fever, headache, muscle aches and pains, red eyes, swollen lymph glands and gastro-intestinal symptoms appear within several days.  A rash appears on the arms, legs and body and lasts for a few days.  Pneumonia and a resulting cough are common.  If untreated, between 1 to 60 percent of the cases will die depending on the strain of the infecting germ. 

Preventative Measures

There are currently no vaccines available for this illness.  The best preventive measure is to avoid mite bites through the proper use of insect repellents, self examination after being in areas known to harbour mites where this infection is present, and wearing protective clothing.

Treatment

Tetracyclines (e.g., doxycycline) and cloramphenicol antibiotics are effective. However, if given early in the illness, a relapse may follow when treatment is completed.  A second course of treatment may be necessary.

Medications

Where Does It Commonly Occur?

Scrub typhus is usually found in central, eastern and southeastern Asia, specifically in Korea, China, Taiwan, Japan, Pakistan, India, Thailand, Malaysia, and northern areas of Australia.