Predictor variables for and complications associated with Streptococcus equi subsp equi infection in horses.

The study investigates the predictor factors and complications linked to Streptococcus equi subsp equi infection, known as strangles, in horses. Through a retrospective case-control study, the research looks into variables associated with strangles, clinical symptoms, disease complications and outcomes.

Research Methodology

• The study involved a retrospective case-control research involving 108 horses with strangles and 215 horses without the infection as the control group.
• The research analyzed medical records from the period January 2005 to July 2012.
• The cases comprised horses displaying clinical indications of strangles, linked to a confirmed strangles outbreak or were detected positively for S equi through PCR assay or bacterial culture.
• The control group involved horses with pyrexia, but did not exhibit other case criteria.
• The collected data for cases and controls included signalment, clinical symptoms, diagnostic test findings, and disease complications and the resultant outcomes.

Study Results

• The study indicated that not all infected horses showed clinical signs of strangles.
• Some of the predictor variables linked to strangles include mucopurulent nasal discharge and exterior abscesses in the pharyngeal region.
• Strangles were more prevalent during spring than summer.
• Purpura hemorrhagica was more likely to develop in horses with anemia than those without.
• No risk factors associated with the development of guttural pouch empyema or metastatic abscesses were identified.

Conclusion and Recommendations

• The results of the research demonstrated that not all horses infected with S equi manifest clinical indications of strangles implying that identification of S equi infection cannot be solely determined by clinical signs.
• Based on these findings, the researchers recommend conducting guttural pouch endoscopy and lavage with PCR assay of lavage fluid samples for accurate identification of S equi carrier horses.