Strangles is a globally widespread, commonly diagnosed and important infectious disease
of equids caused by
Streptococcus equi
subsp.
equi
. We
performed whole genome sequencing of 19
S. equi
isolates collected from
imported horses at the Japanese border. Of these isolates, 15 isolates were obtained from
clinical cases and 4 were from subclinical cases. The 19 isolates were grouped into 3
Bayesian analysis of population structure (BAPS) groups by the core genome single
nucleotide polymorphism analysis corresponding to exporting country, SeM typing, or
exporter of the horses. The 19 isolates possessed same pathogenic genes regardless of
clinical status in imported horses and no antimicrobial resistance genes. The disease
status of the horses may rather reflect the prior exposure of animals with sub-clinical
infection to
S. equi
.