Scrub typhus: A Retrospective Study at a tertiary health care centre in Central Kerala

Background:Scrub typhus is an acute febrile illness caused by Orientia tsutsugamushi, transmitted by the bite of larvae of Leptotrombidium mites.InAsia, about one million new cases are identified annually and one billion people may be at risk of this disease.It is widespread in Japan, South Korea, India, Nepal, and Australia.lnIndia, there are reports of resurgence of scrub typhus, including Kerala.ltpresents clinically as a non specific febrile illness and is often overlooked.We did a retrospective study to estimate the number of scrub typhus cases diagnosed in our hospital, which is located in Central Kerala.Methodology: A retrospective study was done to find out the number of scrub typhus cases diagnosed either by Scrub Typhus IgM ELISA or Weil Felix test during the period January 2013 to December2014 at Pushpagiri Medical College, Tiruvalla.Results:During the period of study, there were nine cases of scrub typhus, out of which six cases were positive by both ELISA and Weil Felix test, three cases positive only by ELlSA.Scrub typhus accounted for 0.4% of the non specific febrile illnesses, both in 2013 and 2014.It was found that 40% of the undifferentiated febrile illnesses in 2013 and 57% of them in 2014 ,were negative for all serological tests done and, were not tested for scrub typhus.Conclusion: Recent reports from several parts of India, including South India, indicate that there is a resurgence of scrub typhus.Many cases are being reported every year from the Northern and Southern parts of Kerala and very few number of cases from Central Kerala.It is grossly under diagnosed due to its non specific clinical presentation, limited awareness and low index of clinical suspicion.In this scenario of increasing incidence of scrub typhus, it is essential to consider scrub typhus as a differential diagnosis in acutefebrile illnesses.