Scrub typhus: a reemerging infection

Curr Opin Infect Dis. 2020 Oct;33(5):365-371. doi: 10.1097/QCO.0000000000000664.

Abstract

Purpose of review: Scrub typhus, caused by Orientia tsutsugamushi, is a widely neglected disease which is gaining global momentum because of its resurgence patterns. The disease is now being reported in newer regions as well as areas previously endemic areas. In this review, we aim to comprehensively review the data available to assist physicians in making an accurate diagnosis and appropriate management of the disease.

Recent findings: Several diagnostic tests have been developed for confirming scrub typhus. However, there is lack of clarity on which tests are most appropriate in a given clinical scenario. A recent study has demonstrated that in early disease (<7 days) when serological tests remain negative, the quantitative polymerase chain reaction is the most sensitive test. Among the serological tests, both IgM enzyme-linked immunosorbent assay as well as rapid diagnostic tests revealed excellent sensitivities and specificities.

Summary: With the reemergence of scrub typhus, a high degree of clinical suspicion is required to appropriately diagnose this disease which presents as an acute febrile illness. It can progress to develop various complications leading to multi-organ dysfunction syndrome. Mild illness responds well to antibiotic treatment with doxycycline and azithromycin. Further studies are required to determine the most optimal therapy in severe scrub typhus infections and superiority of one drug over the other.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Anti-Bacterial Agents / therapeutic use
  • Antibodies, Bacterial / immunology
  • Azithromycin / therapeutic use
  • Doxycycline / therapeutic use
  • Enzyme-Linked Immunosorbent Assay / methods
  • Female
  • Global Health
  • Humans
  • Male
  • Neglected Diseases / diagnosis
  • Neglected Diseases / therapy
  • Orientia tsutsugamushi / isolation & purification
  • Polymerase Chain Reaction / methods
  • Scrub Typhus / diagnosis*
  • Scrub Typhus / epidemiology
  • Scrub Typhus / therapy*
  • Sensitivity and Specificity
  • Serologic Tests / methods
  • Skin / pathology
  • Travel

Substances

  • Anti-Bacterial Agents
  • Antibodies, Bacterial
  • Azithromycin
  • Doxycycline