A review of the global epidemiology of scrub typhus

Abstract

Scrub typhus is a serious public health problem in the Asia-Pacific area. It threatens one billion people globally, and causes illness in one million people each year. Caused by Orientia tsutsugamushi, scrub typhus can result in severe multiorgan failure with a case fatality rate up to 70% without appropriate treatment. The antigenic heterogeneity of O. tsutsugamushi precludes generic immunity and allows reinfection. As a neglected disease, there is still a large gap in our knowledge of the disease, as evidenced by the sporadic epidemiologic data and other related public health information regarding scrub typhus in its endemic areas. Our objective is to provide a systematic analysis of current epidemiology, prevention and control of scrub typhus in its long-standing endemic areas and recently recognized foci of infection.

Fig 1. Worldwide map of countries with reported scrub typhus cases.

The majority of scrub typhus cases occur in the “tsutsugamushi triangle” in the Asia-Pacific area. Countries with human cases are labeled with a star. [Modified from https://landsatlook.usgs.gov/viewer.html].