Descriptive epidemiology and spatial dynamics of scrub typhus across targeted districts in Madhya Pradesh, India: a pilot study

Scrub typhus cases have been reported in Madhya Pradesh; however, the extent and the distribution of the disease remain unclear. Our aim was to establish evidence for the circulation of Orientia tsutsugamushi , the causative agent of scrub typhus in Madhya Pradesh, and to describe its epidemiology in terms of time, place, and demographics. We established Fever Sentinel Surveillance Sites (FSSS) at four District Hospitals of Madhya Pradesh. All Non-Malarial Acute Undifferentiated fever (NMUAF) cases of three days or more were identified, and their samples were tested for Scrub Typhus by IgM ELISA. For descriptive epidemiology, analysis of time, place, and spatial distribution of scrub typhus positive cases was performed. Spatial pattern of scrub typhus cases was analyzed using Local Indicators of Spatial Association (LISA). Of a total of 1281 individuals screened, 287 were positive for Scrub typhus serology (22.40%) On follow up, three of them died (case fatality rate of 1.04%). More than half of the cases (54.34%) were below 40 years of age, with a mean age of 38.10 years (SD 16.86). There was a slight male preponderance, with 52.61% males and 47.38% females. Spatial analysis of Scrub typhus cases showed that the spatial autocorrelation was positive, suggesting clustering of reported cases during the study duration. Conclusively, our study indicates the substantial burden of Scrub typhus, a neglected tropical disease in Madhya Pradesh. This suggests the public health implications of Scrub typhus and the need for intensifying its surveillance in Madhya Pradesh.