Scrub typhus: Clinical features and diagnosis
- Daniel J Sexton, MD
Daniel J Sexton, MD
- Editor-in-Chief — Infectious Diseases
- Section Editor — Bacterial Infections
- Professor of Medicine
- Duke University Medical Center
Scrub typhus is a mite-borne infectious disease caused by Orientia tsutsugamushi (previously called Rickettsia tsutsugamushi). This disease was first described by the Chinese in the third century, but the first description of its classic features did not appear in the western literature until the end of the nineteenth century. Knowledge about scrub typhus increased dramatically during World War II due to its common occurrence in soldiers fighting on both sides in the Pacific theater.
The epidemiology, clinical features, and diagnosis of scrub typhus will be reviewed here. Treatment of this disorder is discussed separately. (See "Scrub typhus: Treatment and prevention".)
O. tsutsugamushi is a gram-negative coccobacillus that is antigenically distinct from the typhus group rickettsiae. This organism has features that are common to and distinct from other rickettsiae.
●Like all rickettsiae, it cannot be propagated in cell-free media. (See "Biology of Rickettsia rickettsii infection".)
●Unlike other rickettsiae, the trilaminar outer membrane of O. tsutsugamushi is unique in its morphology.
- Walker DH, Feng HM, Popov VL. Rickettsial phospholipase A2 as a pathogenic mechanism in a model of cell injury by typhus and spotted fever group rickettsiae. Am J Trop Med Hyg 2001; 65:936.
- Walsh DS, Myint KS, Kantipong P, et al. Orientia tsutsugamushi in peripheral white blood cells of patients with acute scrub typhus. Am J Trop Med Hyg 2001; 65:899.
- Currie B, O'Connor L, Dwyer B. A new focus of scrub typhus in tropical Australia. Am J Trop Med Hyg 1993; 49:425.
- Balcells ME, Rabagliati R, García P, et al. Endemic scrub typhus-like illness, Chile. Emerg Infect Dis 2011; 17:1659.
- Weitzel T, Dittrich S, López J, et al. Endemic Scrub Typhus in South America. N Engl J Med 2016; 375:954.
- Ghorbani RP, Ghorbani AJ, Jain MK, Walker DH. A case of scrub typhus probably acquired in Africa. Clin Infect Dis 1997; 25:1473.
- Izzard L, Fuller A, Blacksell SD, et al. Isolation of a novel Orientia species (O. chuto sp. nov.) from a patient infected in Dubai. J Clin Microbiol 2010; 48:4404.
- Taylor AJ, Paris DH, Newton PN. A Systematic Review of Mortality from Untreated Scrub Typhus (Orientia tsutsugamushi). PLoS Negl Trop Dis 2015; 9:e0003971.
- Zhang WY, Wang LY, Ding F, et al. Scrub typhus in mainland China, 2006-2012: the need for targeted public health interventions. PLoS Negl Trop Dis 2013; 7:e2493.
- Strickman D, Tanskul P, Eamsila C, Kelly DJ. Prevalence of antibodies to rickettsiae in the human population of suburban Bangkok. Am J Trop Med Hyg 1994; 51:149.
- Park SW, Ha NY, Ryu B, et al. Urbanization of scrub typhus disease in South Korea. PLoS Negl Trop Dis 2015; 9:e0003814.
- LANG WR. A case of Addison's suprarenal syndrome of primary pituitary origin. Med J Aust 1946; 1:335.
- Watt G, Strickman D. Life-threatening scrub typhus in a traveler returning from Thailand. Clin Infect Dis 1994; 18:624.
- Dupon M, Rogues AM, Malou M, et al. Scrub typhus: an imported Rickettsial disease. Infection 1992; 20:153.
- Marschang A, Nothdurft HD, Kumlien S, von Sonnenburg F. Imported rickettsioses in German travelers. Infection 1995; 23:94.
- McDonald JC, MacLean JD, McDade JE. Imported rickettsial disease: clinical and epidemiologic features. Am J Med 1988; 85:799.
- Sonthayanon P, Chierakul W, Wuthiekanun V, et al. Association of high Orientia tsutsugamushi DNA loads with disease of greater severity in adults with scrub typhus. J Clin Microbiol 2009; 47:430.
- Sonthayanon P, Chierakul W, Wuthiekanun V, et al. Rapid diagnosis of scrub typhus in rural Thailand using polymerase chain reaction. Am J Trop Med Hyg 2006; 75:1099.
- Jang MO, Kim JE, Kim UJ, et al. Differences in the clinical presentation and the frequency of complications between elderly and non-elderly scrub typhus patients. Arch Gerontol Geriatr 2014; 58:196.
- Audhya M, Abirami D, Srikanth S. Atypical eschar: An unusual cutaneous manifestation of scrub typhus. J Vector Borne Dis 2015; 52:267.
- Berman SJ, Kundin WD. Scrub typhus in South Vietnam. A study of 87 cases. Ann Intern Med 1973; 79:26.
- Sheehy TW, Hazlett D, Turk RE. Scrub typhus. A comparison of chloramphenicol and tetracycline in its treatment. Arch Intern Med 1973; 132:77.
- Kim SJ, Chung IK, Chung IS, et al. The clinical significance of upper gastrointestinal endoscopy in gastrointestinal vasculitis related to scrub typhus. Endoscopy 2000; 32:950.
- Charoensak A, Chawalparit O, Suttinont C, et al. Scrub typhus: chest radiographic and clinical findings in 130 Thai patients. J Med Assoc Thai 2006; 89:600.
- Aronoff DM, Watt G. Prevalence of relative bradycardia in Orientia tsutsugamushi infection. Am J Trop Med Hyg 2003; 68:477.
- Hazlett DR. Scrub typhus in Vietnam: experience at the 8th Field Hospital. Mil Med 1970; 135:31.
- Machella TE, Forrester JS. Mite or scrub typhus: a clinical and laboratory study of 64 cases. Am J Med Sci 1945; 38:38.
- Silpapojakul K, Ukkachoke C, Krisanapan S, Silpapojakul K. Rickettsial meningitis and encephalitis. Arch Intern Med 1991; 151:1753.
- Premaratna R, Chandrasena TG, Dassayake AS, et al. Acute hearing loss due to scrub typhus: a forgotten complication of a reemerging disease. Clin Infect Dis 2006; 42:e6.
- Chang JH, Ju MS, Chang JE, et al. Pericarditis due to Tsutsugamushi disease. Scand J Infect Dis 2000; 32:101.
- Blacksell SD, Bryant NJ, Paris DH, et al. Scrub typhus serologic testing with the indirect immunofluorescence method as a diagnostic gold standard: a lack of consensus leads to a lot of confusion. Clin Infect Dis 2007; 44:391.
- Jensenius M, Fournier PE, Raoult D. Rickettsioses and the international traveler. Clin Infect Dis 2004; 39:1493.
- Kim IS, Seong SY, Woo SG, et al. High-level expression of a 56-kilodalton protein gene (bor56) of Rickettsia tsutsugamushi Boryong and its application to enzyme-linked immunosorbent assays. J Clin Microbiol 1993; 31:598.
- Kim IS, Seong SY, Woo SG, et al. Rapid diagnosis of scrub typhus by a passive hemagglutination assay using recombinant 56-kilodalton polypeptides. J Clin Microbiol 1993; 31:2057.
- Watt G, Strickman D, Kantipong P, et al. Performance of a dot blot immunoassay for the rapid diagnosis of scrub typhus in a longitudinal case series. J Infect Dis 1998; 177:800.
- Sugita Y, Yamakawa Y, Takahashi K, et al. A polymerase chain reaction system for rapid diagnosis of scrub typhus within six hours. Am J Trop Med Hyg 1993; 49:636.
- Murai K, Okayama A, Horinouchi H, et al. Eradication of Rickettsia tsutsugamushi from patients' blood by chemotherapy, as assessed by the polymerase chain reaction. Am J Trop Med Hyg 1995; 52:325.
- Kim DM, Yun NR, Yang TY, et al. Usefulness of nested PCR for the diagnosis of scrub typhus in clinical practice: A prospective study. Am J Trop Med Hyg 2006; 75:542.
- Kim CM, Cho MK, Kim DM, et al. Accuracy of Conventional PCR Targeting the 16S rRNA Gene with the Ot-16sRF1 and Ot-16sRR1 Primers for Diagnosis of Scrub Typhus: a Case-Control Study. J Clin Microbiol 2016; 54:178.
- Kim DM, Kim HL, Park CY, et al. Clinical usefulness of eschar polymerase chain reaction for the diagnosis of scrub typhus: a prospective study. Clin Infect Dis 2006; 43:1296.
- Phimda K, Hoontrakul S, Suttinont C, et al. Doxycycline versus azithromycin for treatment of leptospirosis and scrub typhus. Antimicrob Agents Chemother 2007; 51:3259.