Prevalence of Streptococcus equi subsp. equi in horses and associated risk factors in the State of Rio Grande do Sul, Brazil

Res Vet Sci. 2016 Feb:104:53-7. doi: 10.1016/j.rvsc.2015.11.009. Epub 2015 Nov 14.

Abstract

The aim of this study was to estimate the prevalence of equine strangles and to identify associated risk factors for this disease through a cross-sectional study of nasal swabs. Nasal swabs (n=1010) from healthy equines (absence of nasal discharge, lymphadenopathy and cough) from 341 farms were plated on 5% blood agar; of these horses, 24 were identified as positive for Streptococcus equi through isolation, PCR and DNA sequencing. The estimated prevalence for individual animals was 2.3%, and for herds, it was 5.86%. Statistical analysis identified the following as associated risk factors: the number of group events that were attended by the equines (PR: 1.06); the sharing of food containers (PR: 3.74); and at least one previous positive diagnosis of strangles on the farm (PR: 3.20). These results constitute an epidemiological contribution to the horse industry and may support measures for the future control of the disease.

Keywords: Adenitis; Epidemiology; Equine; Respiratory; Strangles.

MeSH terms

  • Animals
  • Brazil / epidemiology
  • Cross-Sectional Studies
  • Horse Diseases / epidemiology*
  • Horse Diseases / microbiology
  • Horses
  • Nose / microbiology
  • Polymerase Chain Reaction / veterinary
  • Prevalence
  • Risk Factors
  • Sequence Analysis, DNA / veterinary
  • Streptococcal Infections / epidemiology
  • Streptococcal Infections / microbiology
  • Streptococcal Infections / veterinary*
  • Streptococcus equi / isolation & purification*