Comparison of Streptococcus agalactiae Isolates from Humans and Companion Animals Reveals Genotypic and Phenotypic Differences

Takahiro Maeda; Yuzo Tsuyuki; Tomohiro Fujita; Yasuto Fukushima; Mieko Goto; Haruno Yoshida; Takashi Takahashi

doi:10.7883/yoken.JJID.2019.441

Epidemiological Report

Comparison of Streptococcus agalactiae Isolates from Humans and Companion Animals Reveals Genotypic and Phenotypic Differences

Takahiro Maeda, Yuzo Tsuyuki, Tomohiro Fujita, Yasuto Fukushima, Mieko Goto, Haruno Yoshida, Takashi Takahashi

Author information

Takahiro Maeda
Laboratory of Infectious Diseases, Graduate School of Infection Control Sciences & Kitasato Institute for Life Sciences, Kitasato University, Japan
Yuzo Tsuyuki
Laboratory of Infectious Diseases, Graduate School of Infection Control Sciences & Kitasato Institute for Life Sciences, Kitasato University, Japan
Division of Clinical Laboratory, Sanritsu Zelkova Veterinary Laboratory, Japan
Tomohiro Fujita
Laboratory of Infectious Diseases, Graduate School of Infection Control Sciences & Kitasato Institute for Life Sciences, Kitasato University, Japan
Department of Clinical Laboratory, Kitasato University Medical Center, Japan
Yasuto Fukushima
Laboratory of Infectious Diseases, Graduate School of Infection Control Sciences & Kitasato Institute for Life Sciences, Kitasato University, Japan
Mieko Goto
Laboratory of Infectious Diseases, Graduate School of Infection Control Sciences & Kitasato Institute for Life Sciences, Kitasato University, Japan
Haruno Yoshida
Laboratory of Infectious Diseases, Graduate School of Infection Control Sciences & Kitasato Institute for Life Sciences, Kitasato University, Japan
Takashi Takahashi
Laboratory of Infectious Diseases, Graduate School of Infection Control Sciences & Kitasato Institute for Life Sciences, Kitasato University, Japan

Keywords: Streptococcus agalactiae, non-invasive strains, virulence gene profile, antimicrobial resistance, companion animals

JOURNAL FREE ACCESS

2020 Volume 73 Issue 4 Pages 308-315

DOI https://doi.org/10.7883/yoken.JJID.2019.441

Browse “Advance online publication” version

Details

Abstract

This study assessed whether Streptococcus agalactiae isolates from companion animals differed from those of human origin. Beta-hemolytic S. agalactiae was collected from a veterinary laboratory center and a university hospital. Strains were identified using 16S rRNA amplicon sequencing and amplification of the species-specific dltS gene. We conducted virulence gene profiling, capsular genotyping, determination of clonal complex (CC), and antimicrobial resistance (AMR) phenotyping or genotyping. The 20 non-invasive isolates obtained from animals and 15 non-invasive isolates from adult humans were comparatively analyzed in this study. We found significant differences in the virulence gene profiles of bca-rib-lmb-cylE (40.0% vs. 93.3%) and the possession of bac (30.0% vs. 0%) between animal-origin and human-origin non-invasive strains. We observed a significant difference in the distribution of CC1 between the two non-invasive populations. There were significant differences in the prevalence of tetracycline resistance genotypes (60.0% vs. 20.0%) and absence of AMR genotypes (30.0% vs. 80.0%), and AMR rates of tetracycline (35.0% vs. 0%) and fluoroquinolone (20.0% vs. 66.7%) between the two non-invasive populations. These observations suggest that there were different features, in terms of virulence gene profile, CC, and AMR genotype/phenotype in the non-invasive isolates of animal origin compared to those of human origin.

Corresponding author

Correction information

Register with J-STAGE for free!