Update on strangles cases in the South Island

Published on 3 February 2025.

There have been several confirmed cases of strangles, a bacterial infection caused by Streptococcus equi equi, in the South Island over the past month. Cases have been confirmed in Canterbury, Otago and Southland.

Clinical signs appear quite mild in affected horses, and include dullness, fever, nasal discharge and a cough, with few lymph node abscesses reported. Incubation time is between three and 14 days following exposure. The bacteria is spread via contact with infected horses or contaminated equipment.

All clusters appear contained at the time of writing. Quarantine measures are in place on the affected properties and the veterinarians involved have done and continue to do an excellent job managing this.

At this stage, a common source of infection has not been identified but investigation is ongoing. In most cases, a history of travel of a horse or horses onto affected properties within the incubation time has been reported. Primarily Thoroughbreds and Standardbreds appear to be affected, and most of these cases are in broodmares.

Please remember to keep a vigilant watch for any potential strangles cases and notify your veterinarian of any suspected cases. For more information about strangles, please see the New Zealand Equine Research Foundation  website.

Strangles vaccinations can be administered by your vet. Although vaccination does not confer 100% protection against infection, it can prevent infection and/or minimise severity of signs in some cases. Please contact your local vet for more information about vaccination.

Maintaining good cleanliness and hygiene measures, and avoiding mixing with potentially infected horses, will help to minimise risk to your horses.

Many thanks for your understanding and cooperation. We understand there is some anxiety in the community and will release updated information as it becomes available.

In the meantime, please contact your local vet if you have any concerns.