title: Phylogenetic and Geographic Relationships of Severe Fever With Thrombocytopenia Syndrome Virus in China, South Korea, and Japan.
abstract: BACKGROUND
  Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne acute infectious disease caused by the SFTS virus (SFTSV). SFTS has been reported in China, South Korea, and Japan as a novel Bunyavirus. Although several molecular epidemiology and phylogenetic studies have been performed, the information obtained was limited, because the analyses included no or only a small number of SFTSV strains from Japan.
  
  
  METHODS
  The nucleotide sequences of 75 SFTSV samples in Japan were newly determined directly from the patients' serum samples. In addition, the sequences of 7 strains isolated in vitro were determined and compared with those in the patients' serum samples. More than 90 strains that were identified in China, 1 strain in South Korea, and 50 strains in Japan were phylogenetically analyzed.
  
  
  RESULTS
  The viruses were clustered into 2 clades, which were consistent with the geographic distribution. Three strains identified in Japan were clustered in the Chinese clade, and 4 strains identified in China and 26 in South Korea were clustered in the Japanese clade.
  
  
  CONCLUSIONS
  Two clades of SFTSV may have evolved separately over time. On rare occasions, the viruses were transmitted overseas to the region in which viruses of the other clade were prevalent.
authors.affiliation: Special Pathogens Laboratory, Department of Virology I, National Institute of Infectious Diseases.
authors.forename: Tomoki
authors.initials: T
authors.lastname: Yoshikawa
authors.affiliation: Special Pathogens Laboratory, Department of Virology I, National Institute of Infectious Diseases.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Shimojima
authors.affiliation: Special Pathogens Laboratory, Department of Virology I, National Institute of Infectious Diseases.
authors.forename: Shuetsu
authors.initials: S
authors.lastname: Fukushi
authors.affiliation: Special Pathogens Laboratory, Department of Virology I, National Institute of Infectious Diseases.
authors.forename: Hideki
authors.initials: H
authors.lastname: Tani
authors.affiliation: Special Pathogens Laboratory, Department of Virology I, National Institute of Infectious Diseases.
authors.forename: Aiko
authors.initials: A
authors.lastname: Fukuma
authors.affiliation: Special Pathogens Laboratory, Department of Virology I, National Institute of Infectious Diseases.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Taniguchi
authors.affiliation: Special Pathogens Laboratory, Department of Virology I, National Institute of Infectious Diseases.
authors.forename: Harpal
authors.initials: H
authors.lastname: Singh
authors.affiliation: Special Pathogens Laboratory, Department of Virology I, National Institute of Infectious Diseases.
authors.forename: Yuto
authors.initials: Y
authors.lastname: Suda
authors.affiliation: Yamaguchi Prefectural Institute of Public Health and Environment.
authors.forename: Komei
authors.initials: K
authors.lastname: Shirabe
authors.affiliation: Yamaguchi Prefectural Institute of Public Health and Environment.
authors.forename: Shoichi
authors.initials: S
authors.lastname: Toda
authors.affiliation: Hiroshima Prefectural Technology Research Institute, Public Health and Environment Center.
authors.forename: Yukie
authors.initials: Y
authors.lastname: Shimazu
authors.affiliation: Miyazaki Prefectural Institute for Public Health and Environment.
authors.forename: Taro
authors.initials: T
authors.lastname: Nomachi
authors.affiliation: Kagoshima Prefectural Institute for Environmental Research and Public Health.
authors.forename: Mutsuyo
authors.initials: M
authors.lastname: Gokuden
authors.affiliation: The Public Institute of Kochi Prefecture.
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Morimitsu
authors.affiliation: Saga Prefectural Institute of Public Health and Pharmaceutical Research.
authors.forename: Katsuyuki
authors.initials: K
authors.lastname: Ando
authors.affiliation: Nagasaki Prefectural Institute for Environmental Research and Public Health, Omura-shi.
authors.forename: Akira
authors.initials: A
authors.lastname: Yoshikawa
authors.affiliation: Ehime Prefectural Institute of Public Health and Environmental Science, Matsuyama-shi.
authors.forename: Miki
authors.initials: M
authors.lastname: Kan
authors.affiliation: Tokushima Prefectural Public Health, Pharmaceutical and Environmental Sciences Centre.
authors.forename: Marina
authors.initials: M
authors.lastname: Uramoto
authors.affiliation: Kumamoto Prefectural Institute of Public Health and Environmental Science, Uto-shi.
authors.forename: Hideo
authors.initials: H
authors.lastname: Osako
authors.affiliation: Okayama Prefectural Institute for Public Health and Environmental Science.
authors.forename: Kouji
authors.initials: K
authors.lastname: Kida
authors.affiliation: Shimane Prefectural Institute of Public Health and Environmental Science, Matsue-shi.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Takimoto
authors.affiliation: Public Health Science Research Center, Hyogo Prefectural Institute of Public Health and Consumer Sciences, Hyogo-ku Kobe-shi.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Kitamoto
authors.affiliation: Wakayama Prefectural Research Center of Environment and Public Health.
authors.forename: Fumio
authors.initials: F
authors.lastname: Terasoma
authors.affiliation: Oita Prefectural Institute of Health and Environment.
authors.forename: Akiko
authors.initials: A
authors.lastname: Honda
authors.affiliation: Laboratory of Veterinary Microbiology, Joint Faculty of Veterinary Medicine, Yamaguchi University.
authors.forename: Ken
authors.initials: K
authors.lastname: Maeda
authors.affiliation: Department of Hematology, Yamaguchi Grand Medical Center, Hofu-shi.
authors.forename: Toru
authors.initials: T
authors.lastname: Takahashi
authors.affiliation: Infectious Disease Surveillance Center, National Institute of Infectious Diseases.
authors.forename: Takuya
authors.initials: T
authors.lastname: Yamagishi
authors.affiliation: Infectious Disease Surveillance Center, National Institute of Infectious Diseases.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Oishi
authors.affiliation: Department of Veterinary Science, National Institute of Infectious Diseases, Tokyo, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Morikawa
authors.affiliation: Special Pathogens Laboratory, Department of Virology I, National Institute of Infectious Diseases.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Saijo
mesh_terms: D001483:Base Sequence; D002044:Bunyaviridae Infections / Q000097:blood / Q000453:epidemiology / Q000821:virology*; D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D018076:DNA, Complementary / Q000737:chemistry; D004279:DNA, Viral / Q000737:chemistry; D005334:Fever / Q000473:pathology*; D016679:Genome, Viral; D006801:Humans; D007564:Japan / Q000453:epidemiology; D016856:Phlebovirus / Q000145:classification / Q000235:genetics*; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics / Q000302:isolation & purification; D056910:Republic of Korea / Q000453:epidemiology; D017282:Tick-Borne Diseases / Q000453:epidemiology / Q000821:virology
chemical_list: D018076:DNA, Complementary; D004279:DNA, Viral; D012367:RNA, Viral
keywords: Bunyavirus; SFTS; SFTS virus; severe fever with thrombocytopenia syndrome; tick-borne virus infection