title: Evolution and virulence of Panton-Valentine leukocidin-positive ST30 methicillin-resistant Staphylococcus aureus in the past 30 years in Japan.
abstract: Methicillin-resistant Staphylococcus aureus (MRSA) includes hospital-acquired MRSA (HAMRSA) and community-acquired MRSA (CA-MRSA). Panton-Valentine leukocidin (PVL)-positive multilocus sequence type 30 (ST30) MRSA is one of worldwide CA-MRSA, which has also persisted in Japan since the 1980s. However, unexpectedly, it was not the same ST30 clone throughout. Before 2000, it was HA-MRSA with spa43 and ψSa3sea (phage Sa3 carrying the sea gene) and only one PVL-positive MRSA in Japan; in the 1980s, ST30 MRSA accounted for 23.5% of HA-MRSA, showed multidrug resistance, had high MICs for oxacillin and imipenem, and caused decubitus and pneumonia in hospitalized patients. A dynamic clonal change (spa43/ψSa3sea→ spa19) occurred around 2000-2002. A rare spa43/ψSa3sea/SCCmecI-IE25923 genotype also emerged. After 2002, the prevalent spa19 clone was CA-MRSA; it accounted for only 0.3% (or less) of MRSA in hospitals but 7.6% of CA-MRSA. Since 2007, PVL-positive CA-MRSA with other ST types (such as ST8, ST22, and ST59) also emerged in Japan, albeit at a low frequency. ST30/spa19 CA-MRSA occasionally caused severe invasive infections and a novel ST1335/spa19 genotype emerged. These ST30/spa19 CA-MRSA and variants were identified by pulsed field gel electrophoresis. Further analysis revealed that PVL-positive ST30/spa19 CA-MRSA is a highlyvirulent, successful clone, having a potential of clonal expansion.
authors.affiliation: Division of Bacteriology, Department of Infectious Disease Control and International Medicine, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan.
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Isobe
authors.forename: Tomomi
authors.initials: T
authors.lastname: Takano
authors.forename: Akihito
authors.initials: A
authors.lastname: Nishiyama
authors.forename: Wei-Chun
authors.initials: WC
authors.lastname: Hung
authors.forename: Shuichi
authors.initials: S
authors.lastname: Kuniyuki
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Shibuya
authors.forename: Ivan
authors.initials: I
authors.lastname: Reva
authors.forename: Shizuka
authors.initials: S
authors.lastname: Yabe
authors.forename: Yasuhisa
authors.initials: Y
authors.lastname: Iwao
authors.forename: Wataru
authors.initials: W
authors.lastname: Higuchi
authors.forename: Olga E
authors.initials: OE
authors.lastname: Khokhlova
authors.forename: Takeshi
authors.initials: T
authors.lastname: Okubo
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Yamamoto
mesh_terms: D000293:Adolescent; D000328:Adult; D001427:Bacterial Toxins / Q000235:genetics*; D002460:Cell Line; D002648:Child; D002675:Child, Preschool; D024901:Drug Resistance, Multiple, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D019143:Evolution, Molecular; D005098:Exotoxins / Q000235:genetics*; D005260:Female; D005798:Genes, Bacterial; D008040:Genetic Linkage; D049673:History, 20th Century; D049674:History, 21st Century; D054884:Host-Pathogen Interactions; D006801:Humans; D007223:Infant; D007956:Leukocidins / Q000235:genetics*; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D008875:Middle Aged; D010641:Phenotype; D010802:Phylogeny; D013203:Staphylococcal Infections / Q000266:history / Q000382:microbiology*; D014158:Transcription, Genetic; D014774:Virulence / Q000235:genetics
chemical_list: D001427:Bacterial Toxins; D005098:Exotoxins; D007956:Leukocidins; C078284:Panton-Valentine leukocidin