title: Laboratory diagnosis of two scrub typhus outbreaks at Camp Fuji, Japan in 2000 and 2001 by enzyme-linked immunosorbent assay, rapid flow assay, and Western blot assay using outer membrane 56-kD recombinant proteins.
abstract: Two scrub typhus outbreaks occurred among U.S. Marines training at Camp Fuji, Japan, between October 25 and November 3, 2000 and October 17 and November 30, 2001. Nine cases in approximately 800 Marines in 2000 and eight cases in approximately 900 Marines in 2001 (approximate attack rates = 1.1% and 0.9%, respectively) reported with signs and symptoms of fever, rash, headache, lymphadenopathy, myalgia, and eschar. Serologies and rapid response to doxycycline treatment indicated they had scrub typhus. Sixty-four convalescent serum samples (18 suspected cases and 46 negative controls) from U.S. Marines training at Camp Fuji during the outbreaks were assessed by enzyme-linked immunosorbent assay (ELISA), rapid flow assay (RFA), and Western blot assay for evidence of infection with Orientia tsutsugamushi, the causative agent of scrub typhus. All but one suspected case had serologic evidence of scrub typhus and all 46 control sera were non-reactive to O. tsutsugamushi antigens. The recombinant 56-kD antigen (r56) from the Karp, Kato and Gilliam strains of O. tsutsugamushi in an ELISA format provided better results than Karp r56 alone (ELISA and RFA) or whole cell antigen preparation from Karp, Kato and Gilliam (ELISA).
authors.affiliation: Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, Maryland 20910-7500, USA.
authors.forename: Ju
authors.initials: J
authors.lastname: Jiang
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Marienau
authors.forename: Laurel A
authors.initials: LA
authors.lastname: May
authors.forename: H James
authors.initials: HJ
authors.lastname: Beecham
authors.forename: Ray
authors.initials: R
authors.lastname: Wilkinson
authors.forename: Wei-Mei
authors.initials: WM
authors.lastname: Ching
authors.forename: Allen L
authors.initials: AL
authors.lastname: Richards
mesh_terms: D000328:Adult; D000942:Antigens, Bacterial / Q000097:blood / Q000276:immunology; D001425:Bacterial Outer Membrane Proteins / Q000097:blood / Q000276:immunology*; D015153:Blotting, Western / Q000379:methods*; D004196:Disease Outbreaks; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008889:Military Personnel; D012285:Orientia tsutsugamushi / Q000737:chemistry / Q000276:immunology; D011994:Recombinant Proteins / Q000276:immunology*; D012612:Scrub Typhus / Q000175:diagnosis* / Q000453:epidemiology*; D012680:Sensitivity and Specificity; D013997:Time Factors; D014481:United States / Q000208:ethnology
chemical_list: D000942:Antigens, Bacterial; D001425:Bacterial Outer Membrane Proteins; D011994:Recombinant Proteins