Emergence of Scrub Typhus in Kerala: A Review in the Context of Escalating Cases
Abstract
Scrub typhus (ST) is an emerging vector-borne zoonotic disease. It is caused by the bacterium Orientia tsutsugamushi and transmitted to humans through the bite of infected trombiculid chigger mites. An estimated one billion people are at risk of contracting scrub typhus, with roughly one million active cases occurring globally each year. The WHO has designated scrub typhus as a seriously under-acknowledged, neglected public health threat in the Asia-Pacific region. In India, scrub typhus is reportedly resurging across multiple regions, spanning the northern, northeastern, western, and southern states. In Kerala, since its first documented report in 1998, there has been a regular hike in infection and fatality rates all through the years. Of all the districts, Thiruvananthapuram comes with 74.0% of cases and 51.0% of deaths. The highest case incidence and death in Thiruvananthapuram could be attributed to the capital city having been infected from military camps long ago and remaining undetected for a long period, by which time the disease must have spread to a wider area in the district. It must be from Thiruvananthapuram; the disease eventually spread to other areas of Kerala. Scrub typhus has undoubtedly become a critical public health crisis in Kerala. Although awareness of the disease is steadily increasing, more medical and administrative efforts are needed to deal with the threat and to contain its rapid advance. Most existing studies on ST in Kerala focus primarily on hospital-based research. There is a lack of in-depth research into the disease’s spatio-temporal epidemiological risk factors, including systemic complications, climatic drivers, and most importantly, ecological and entomological factors. This review examines the epidemiology, geographic distribution, and seasonal dynamics of scrub typhus in Kerala.
DOI: https://doi.org/10.24321/0019.5138.202667
How to cite this article:
R Rajendran, K Regu, M S Sasi, S N Sharma. Emergence of Scrub Typhus in Kerala: A Review
in the Context of Escalating Cases. J Commun Dis. 2026;58(3):172-182.
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