A case of classical tsutsugamushi disease confirmed after an interval of 15 years in Akita Prefecture, Japan]

We report the confirmation of classical tsutsugamushi disease in August 2008. A 17-year-old woman seen for fever and eschar on the back reported having been bitten by an insect nine days earlier while fishing on the Omonogawa river. The suspected culprit was Leptotrombidium akamushi. During convalescence serum IgM and IgG antibody titers rose significantly against the Kato serotype antigen in indirect immunoperoxidase staining. Epidemiology, clinical symptoms and the antibodies detected suggested classical tsutsugamushi disease infection. Such disease transmitted by L. akamushi have not been reported since 1993 in Akita Prefecture. The public should thus be informed about Orientia tsutsugamushi prevention, in case such disease re-care in this area in the future.