The following background information on Scrub typhus in India is abstracted from Gideon www.GideonOnline.com and the Gideon e-book series. 
Rickettsia tsutsugamushi is one of seven Rickettsia and Rickettsia-like organisms which have been associated with human infection in India (the others are Rickettsia sibirica, Rickettsia conorii subsp. indica, Candidatus Rickettsia kellyi, Rickettsia typhi, Rickettsia prowazekii and Coxiella burnetii)
Epidemics of scrub typhus were previously reported among troops stationed in the north and east.
Risk factors include living close to bushes and wood piles, work on farms, observation of rodents at home and at work, and raising domestic animals (Darjeeling, West Bengal, 2009 publication)
– Three cases of imported scrub typhus were reported in the United States during 1983 to 1988 – all originating in India.
– In 2002, a Belgian traveler developed scrub typhus following a trip to India.
17 fatal cases were reported in Himachal during 2001 to 2002.
– 21 cases (3 fatal) were reported in Himchal Pradesh during 2004.
– Nine cases were confirmed in Uttarakhand (2010 publication)
– 29 cases were reported from a hospital in Manipal, Karnataka during 2009.
24.1% of febrile hospitalized patients in Vellore (2006 publication)
15% of children below age 14 hospitalized for fever in Tamil Nadu (2003 to 2004)
14.3% of children hospitalized with fever and at least one suggestive feature of rickettsial infection (central India, 2011 publication)
37.5% of febrile malaria-negative patients in Tamil Nadu in 2004, and 9.2% in 2005
47.5% of patients hospitalized for acute undifferentiated febrile illness in Vellore, Tamil Nadu (2010 publication)
The principal vector is Leptotrombidium deliense.
– Schoengastiella ligula mites infesting shrews (Suncus murinus) were identified as vectors during an outbreak in Kurseong, Darjeeling.
2001 to 2002 – An outbreak (28 cases, 3 fatal) was reported in Tamil Nadu.
2003 – An outbreak (225 cases, 19 fatal) was reported in Himachal Pradesh.
2006 to 2008 – An outbreak (50 cases) was reported in Pondicherry.
2007 – An outbreak (38 cases) was reported in Bishnupur district, Manipur.
2009 to 2010 – An outbreak (80 cases, 5 fatal) was reported in Meghalaya.
2011 – Outbreaks were reported in Himachal Pradesh (200 cases, 13 fatal) and Nagaland (9 cases, 3 fatal).
1. Berger SA. Infectious Diseases of India, 2011. 480 pp, 65 graphs, 3503 references. Gideon e-books, http://www.gideononline.com/ebooks/country/infectious-diseases-of-india/
Reproduced on ProMED