MIDRP Overview History & Achievements Current Research Efforts External Programs

Program Overview:
Scrub typhus, also known as chigger-borne rickettsiosis, tsutsugamushi disease, tropical or rural typhus, is caused by being bitten by mites infected with Orientia tsutsugamushi. Geographic distribution of the disease occurs within an area of about 13 million square kilometers of Asia, Northern Australia and the Pacific Islands. There is no typical ecology for this disease. Scrub typhus is an acute febrile illness that can present as a mild or severe affliction depending on the Orientia strain and the condition of the patient. The disease typically presents with maculopapular rash, eschar, headache, and lymphadenopathy. Confusion and cough may develop, and pharyngitis and hearing loss have been noted in some cases. A dramatic response to tetracycline is common. Accurate diagnosis of scrub typhus is essential, since a fatal course is possible without appropriate antibiotic treatment. About 25 to 50% of scrub typhus cases occur in children. The growing popularity of eco-tourism in endemic areas has resulted in this disease being increasingly diagnosed in European and American tourists after returning home. Scrub typhus, was a leading cause of morbidity and mortality in the Asia-Pacific Theater during WWII (5,441 cases, 283 deaths among U.S. Army personnel) and the second leading cause of Fever of Unknown Origin during the Vietnam War. This arthropod-borne disease is a significant military problem for deployed forces as has been exemplified by two outbreaks among U.S. marines training at Camp Fuji, Japan (2000, 2001). Reports of antibiotic-resistant scrub typhus among individuals living in Northern Thailand and breakthrough infections among US forces (JTF-FA) on doxycycline prophylaxis in Indochina may suggest that antibiotic treatment/prophylaxis may be less effective in some cases. Thus there is a need for a vaccine to protect against infection. However, due to the absence of a commercial partner with interest in the development of a Scrub typhus vaccine, this Program Area is focused on maintaining the DoD rickettsial diseases research core capability.

Diarrhea Prevention | Rickettsial Disease | Wound Infection Research