Strangles Control Measures

Immediate quarantine of premises that halts equine transport on or off the affected premises to eliminate further disease spread.

  • Horses that are identified to have confirmed S. equi disease must be located in an isolation area that is properly designated as such (“dirty” or “strangles cases”). This will allow caregivers to have major areas for horse handling and “clean” and “affected” areas.

Determine whether recovering horses are infectious.

  • Three nasopharyngeal lavages (preferably) collected at weekly intervals for 3 weeks; samples should be tested using microbiological culture and PCR testing.
  • Test-negative horses are “clean” of infection.

Determine whether apparently healthy horses are S. equi positive.

  • Upper airway endoscopy to determine whether there is the presence of disease.

Eliminate S. equi from guttural pouches of affected horses.

  • Endoscopically guided guttural pouch lavage with isotonic, sterile fluid to remove mucous or chondroid accumulation; manual removal of chondroids may be required if lavage alone is unsuccessful.
  • Systemic and local antibiotic therapy to eliminate S. equi infection.


Establishment of an isolation area and protocols to prevent indirect cross-infection of S. equi to clean areas.

  • Caretakers should have dedicated barrier clothing and instruments. Avoid simultaneous contact with horses. Manage affected horses after clean horses and clean areas.
  • After removal of organic debris, all areas should be cleaned and disinfected.
  • Manure and general waste should be composted in an isolated area.
  • Water troughs should be cleaned daily.
  • Horse transportation vehicles should be cleaned after every use.