title: Characteristics of group B Streptococcus isolated from infants with invasive infections: a population-based study in Japan.
abstract: Group B Streptococcus (GBS) is one of the leading causes of neonatal bacterial infections. Population-based surveillance of GBS-related invasive diseases among newborns and infants from 10 prefectures in Japan was performed between 2007 and 2012. The characteristics of cases and isolated GBS are described in this study. The incidence rate of GBS-related invasive diseases was 0.13 per 1,000 live births. Analysis of GBS samples obtained from 60 invasive cases showed that the most frequent serotypes were III (48.3%), Ia (30.0%), and Ib (10.0%). All isolates were susceptible to penicillin G, ampicillin, cefotaxime, imipenem, and panipenem. However, 14, 2, and 7 isolates were resistant to erythromycin, clindamycin, and both erythromycin and clindamycin, respectively. Multilocus sequence typing revealed that GBS sequence type (ST) 23, ST17, and ST335 caused higher incidences of meningitis. These data show that serotypes III, Ia, and Ib together caused more than 80% of invasive infections in Japanese infants, and that GBS strains are still susceptible to β-lactam antibiotics.
authors.affiliation: Department of Bacteriology I, National Institute of Infectious Diseases.
authors.forename: Bin
authors.initials: B
authors.lastname: Chang
authors.forename: Akihito
authors.initials: A
authors.lastname: Wada
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Hosoya
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Oishi
authors.forename: Naruhiko
authors.initials: N
authors.lastname: Ishiwada
authors.forename: Megumi
authors.initials: M
authors.lastname: Oda
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Sato
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Terauchi
authors.forename: Kenji
authors.initials: K
authors.lastname: Okada
authors.forename: Junichiro
authors.initials: J
authors.lastname: Nishi
authors.forename: Hideki
authors.initials: H
authors.lastname: Akeda
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Kamiya
authors.forename: Makoto
authors.initials: M
authors.lastname: Ohnishi
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Ihara
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016470:Bacteremia / Q000453:epidemiology / Q000382:microbiology*; D005260:Female; D005838:Genotype; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007564:Japan; D008297:Male; D016920:Meningitis, Bacterial / Q000453:epidemiology / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D058885:Multilocus Sequence Typing; D065288:Serogroup; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology*; D013292:Streptococcus agalactiae / Q000145:classification* / Q000302:isolation & purification*
chemical_list: D000900:Anti-Bacterial Agents