title: Acute tick-borne rickettsiosis caused by Rickettsia heilongjiangensis in Russian Far East.
abstract: An acute tick-borne rickettsiosis caused by Rickettsia heilongjiangensis was diagnosed in 13 patients from the Russian Far East in 2002. We amplified and sequenced four portions of three rickettsial genes from the patients' skin biopsy results and blood samples and showed that the amplified rickettsial genes belong to R. heilongjiangensis, which was recently isolated from Dermacentor sylvarum ticks in nearby regions of China. This rickettsia, belonging to subgroup of R. japonica, was previously suggested to be pathogenic for humans on the basis of serologic findings. We tested serum samples with different rickettsial antigens from 11 patients and confirmed increasing titers of immunoglobulin (Ig) G and IgM to spotted fever group rickettsiae, including R. heilongjiangensis. Clinical and epidemiologic data on these patients show that this disease is similar to other tick-borne rickettsioses.
authors.affiliation: Laboratory of Rickettsial Ecology, Gamaleya Research Institute of Epidemiology and Microbiology, Moscow, Russia. olegusss1@mail.ru
authors.forename: Oleg Y
authors.initials: OY
authors.lastname: Mediannikov
authors.forename: Yuri
authors.initials: Y
authors.lastname: Sidelnikov
authors.forename: Leonid
authors.initials: L
authors.lastname: Ivanov
authors.forename: Eugenia
authors.initials: E
authors.lastname: Mokretsova
authors.forename: Pierre-Edouard
authors.initials: PE
authors.lastname: Fournier
authors.forename: Irina
authors.initials: I
authors.lastname: Tarasevich
authors.forename: Didier
authors.initials: D
authors.lastname: Raoult
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood; D001426:Bacterial Proteins / Q000235:genetics; D004269:DNA, Bacterial / Q000032:analysis / Q000302:isolation & purification; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012281:Rickettsia / Q000145:classification* / Q000235:genetics / Q000276:immunology; D012282:Rickettsia Infections / Q000453:epidemiology* / Q000382:microbiology / Q000503:physiopathology; D017422:Sequence Analysis, DNA; D012800:Siberia / Q000453:epidemiology; D017282:Tick-Borne Diseases / Q000453:epidemiology* / Q000382:microbiology / Q000503:physiopathology
chemical_list: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D004269:DNA, Bacterial