An Overview of the Clinical Profile and Risk Factors Associated with Severe Scrub Typhus Infection: A Hospital Based Study in Coimbatore

Scrub typhus (ST) is an important cause of acute undifferentiated febrile illness. ST is caused by Orientia tsutsugamushi transmitted by the bite of a trombiculid mite. It is endemic in East Asia, the South Pacific, and the Indian subcontinent. In India, ST accounts for about 23% of all febrile illnesses. This study aimed to assess the clinical profile of ST and associated risk factors.

This cross-sectional study was conducted on 47 participants in the general medicine department of a tertiary medical college hospital in Coimbatore, south India from January 2020 to June 2021. All the participants suffered from fever and diagnosed with ST based on seropositivity of IgM enzyme linked immunosorbent assay (ELISA). Complete blood count, renal and liver function tests, and chest X-ray were performed. All the participants were admitted to the hospital and followed up.

The participants' age ranged from 18-80 years with a mean age of 48.40 years.  Most ST cases occurred during January (48.9%). Fever was the common symptom (95.7%), while eschar was reported in only 19.1% of the individuals. Thrombocytopenia was detected in 12.8% of ST patients. Hypoalbuminemia was reported in 80% of those with hepatic dysfunction, and anemia was present in 28% of those with acute kidney injury.

This disease could present as a severe illness even in non-ICU (intensive care units) settings, and a high degree of suspicion is necessary for diagnosing and treating ST patients in endemic areas.