Scrub Typhus

恙虫病

Evidence-backed information EN 5/7 applicable sections · ZH 5/7 applicable sections Updated Oct 23, 2026

Scrub typhus is a neglected bacterial zoonosis of the Asia-Pacific region that increasingly appears beyond its traditional Tsutsugamushi triangle, threatening roughly one billion people and causing about one million illnesses yearly ^[1]^[2]. Globally, pooled seroprevalence is approximately one quarter of tested samples, with eschar present in about one third of positive cases ^[3]. Clinical diagnosis is difficult due to non-specific features, and public-health impact is likely underestimated where laboratory confirmation is limited ^[1]^[4].

Read the full clinical and epidemiological profile 6

Definition

Scrub typhus is a bacterial zoonotic disease caused by Orientia tsutsugamushi, classified among neglected acute febrile infections transmitted via arthropod vectors ^[1]^[2]^[4]. It is a widespread zoonosis across Asia and the Pacific Islands and is recognized as a globally distributed neglected infection ^[1]^[4].

Clinical features

The illness is an acute febrile disease with generally non-specific signs and symptoms, ranging from subclinical infection to organ failure or fatal outcome ^[4]. Because clinical presentations overlap with other febrile infections, laboratory testing is essential, though point-of-care immunochromatographic tests show moderate sensitivity and better utility for confirming rather than excluding disease ^[5]^[4].

Epidemiology

Scrub typhus is a serious public-health problem concentrated in the Asia-Pacific but now reported outside the Tsutsugamushi triangle ^[3]^[2]. A meta-analysis of 181 studies estimated a pooled global seroprevalence of 24.93%, with similar rates in males (50.23%) and females (48.84%) ^[3]. It threatens one billion people and causes about one million cases annually, with case fatality reaching 70% absent appropriate treatment ^[2].

Transmission

Scrub typhus is a zoonotic infection acquired through arthropod vectors, consistent with bacterial zoonoses transmitted by vectors rather than direct contact or consumption alone ^[1]^[4]. The disease is maintained in nature as a zoonosis across Asia and Pacific Islands ^[4].

Prevention

Strengthening surveillance and implementing disease control measures are recommended in affected regions given the documented burden and spread beyond endemic areas ^[3]. Control strategies must account for antigenic heterogeneity of O. tsutsugamushi that permits reinfection and complicates generic immunity ^[2]. Improved diagnostic access, including point-of-care tests in resource-limited settings, supports patient management where sophisticated laboratories are unavailable ^[5].

References

1 Chikeka I et al. Neglected bacterial zoonoses. Clin Microbiol Infect. 2015 May. PMID: 25964152. doi: 10.1016/j.cmi.2015.04.022. PubMed: https://pubmed.ncbi.nlm.nih.gov/25964152/
2 Xu G et al. A review of the global epidemiology of scrub typhus. PLoS Negl Trop Dis. 2017 Nov. PMID: 29099844. doi: 10.1371/journal.pntd.0006062. PubMed: https://pubmed.ncbi.nlm.nih.gov/29099844/
3 Dasgupta S et al. Global seroprevalence of scrub typhus: a systematic review and meta-analysis. Sci Rep. 2024 May 13. PMID: 38740885. doi: 10.1038/s41598-024-61555-9. PubMed: https://pubmed.ncbi.nlm.nih.gov/38740885/
4 Mahajan SK et al. Scrub typhus. J Assoc Physicians India. 2005 Nov. PMID: 16515236. PubMed: https://pubmed.ncbi.nlm.nih.gov/16515236/
5 Saraswati K et al. Scrub typhus point-of-care testing: A systematic review and meta-analysis. PLoS Negl Trop Dis. 2018 Mar. PMID: 29579046. doi: 10.1371/journal.pntd.0006330. PubMed: https://pubmed.ncbi.nlm.nih.gov/29579046/