Seroprevalence of Scrub typhus among Febrile Patients in a Tertiary Care Hospital in Thiruvananthapuram, Kerala

Scrub typhus is a rickettsial infection caused by Orientia tsutsugamushi that belongs to the family Rickettsiaceae and transmitted by some species of trombiculid mites chiggers, particularly a Leptotrombidium deliense. A necrotic eschar at the inoculating site of the mite is pathognomic of Scrub typhus. Scrub typhus is a zoonosis and is a widespread disease in Asia and Pacific Islands. Fever is the most common symptom of Scrub typhus and in endemic areas; it is one of the causes of fever of unknown origin. In order to understand the clinical spectrum and its prevalence, a retrospective study was conducted in patients admitted with acute febrile illness in Govt. Medical College, Thiruvananthapuram over a period of 1 year. A total of 1268 serum samples were screened for Scrub typhus by IgM enzyme-linked immunosorbent assay. About 217 patients were positive among which 118 were male and 99 were female. The seroprevalence of Scrub typhus was 17.11%. There were antigenic cross reaction with IgM leptospirosis for 11 cases and IgM dengue for 2 cases. Effective management and early administration of antibiotics will help to prevent the complications and mortality associated with Scrub typhus.