Scrub Typhus - A new threat

Scrub Typhus, or tsutsugamushi disease is a febrile illness caused by bacter ia of the family rickettsiaceae and named Orientia tsutsugamushi. Scrub typhus is endemic to a geographically distinct region, the so-called tsutsugamushi triangle, which includes Japan, Taiwan, China, and South Korea.
It also occurs in nepal, northern Pakistan, Papua new Guinea, and the Australian states of Queensland and northern new South Wales. In India, the disease had occurred among troops during World War II in Assam and West Bengal, and in the 1965 Indo-Pak war. There was a resurgence of the disease in 1990 in a unit of an army deployed at the Pakistan border of india. It is known to occur all over India, including Southern
India and northern India. However, the reported number of cases of Scrub typhus from different parts of the country particularly from large tertiary care hospitals do not give a true picture of prevalence of scrub typhus in the country. As yet there are not many community based studies in our country.One such community based study involving several districts in Tamil nadu showed that scrub typhus and rickettsial diseases were widely distributed in the state.In this context the repor t of outbreak of scrub typhus
in Pondicherr y and in the current issue of the Journal meaningful. In this report the diverse clinical and laboratory manifestations of scrub typhus are described. The diagnosis was based on the presence of eschar and/or positive Weil Felix test with a titre of > 1:80.In scrub typhus, an eschar approximately 5 to 20 mm in diameter is formed at the site bitten by trombiculid mites, and this may be considered the most important clinical finding for the diagnosis of scrub typhus. The site bitten by chiggers is initially a papule followed by a blistered ulcer, and this is then covered with a black crust; the border of the eschar is surrounded by reddish erythema. Such a typical eschar is formed at the time when symptoms are manifested.