Key Takeaways
- An outbreak of the highly contagious bacterial disease Strangles has been confirmed on 11 thoroughbred properties in Waikato and one in Auckland.
- The disease causes fever, respiratory distress and breathing problems in horses, ponies and donkeys, though it is rarely fatal.
- New Zealand Thoroughbred Racing (NZTR) has postponed race trials, instituted mandatory five‑day temperature monitoring, and requires blood tests and health declarations for horses from the affected Waikato region before they may compete.
- Transport operators, breeding farms and racing clubs have agreed to halt movement of horses from other regions while the outbreak persists, aiming to curb further spread.
- Although Strangles is not a notifiable condition in New Zealand, industry leaders worry that a prolonged outbreak could damage the country’s reputation as a source of thoroughbred exports, especially to Australia where the disease is notifiable and strict import controls apply.
- Ongoing collaboration among veterinary authorities, industry groups and government agencies is focused on containment, surveillance, and developing clear export‑protocol guidelines to safeguard both domestic racing and international trade.
Outbreak Overview
In early [month], veterinary officials confirmed an outbreak of Strangles—a serious, highly contagious bacterial infection—on 11 thoroughbred farms in the Waikato region and a single property in Auckland. The disease, caused by Streptococcus equi subspecies equi, spreads rapidly through direct horse‑to‑horse contact, shared equipment, or environmental contamination. Because thoroughbreds frequently travel to race meets, training centres, and sales, the close‑quarters environment has facilitated a faster transmission rate than would typically be seen in more isolated equine populations. Authorities have placed all affected premises under strict isolation, prohibiting the movement of horses on or off the properties until clearance is granted.
What Is Strangles?
Strangles manifests primarily as a sudden onset of high fever (often exceeding 38.5 °C), profuse nasal discharge, and swelling of the lymph nodes around the throat and jaw, which can abscess and rupture. Affected horses may exhibit difficulty swallowing, labored breathing, and a characteristic “strangled” cough, giving the disease its name. While mortality is low—usually under 10 % in uncomplicated cases—the illness can lead to secondary pneumonia, guttural pouch infection, or chronic carrier states that pose a continued risk to herd health. Treatment involves antimicrobial therapy, supportive care, and strict biosecurity measures; vaccination exists but is not universally used due to variable efficacy and potential side‑effects.
Geographic Distribution and Affected Properties
The current cluster is concentrated in Waikato, a hub for thoroughbred breeding and training, with one additional case identified in Auckland’s peri‑urban equestrian facilities. Epidemiological tracing suggests that the index case likely originated from a recently imported horse or a shared training venue where biosecurity lapses allowed the pathogen to circulate. Because the affected farms are interconnected through regular movement of yearlings, broodmares, and stallions for sales and training, the disease has shown a propensity to jump between premises despite isolation efforts. Veterinary teams are conducting repeated nasal swabs and blood sampling to monitor shedding and confirm when animals are no longer infectious.
Impact on Racing and Trials
New Zealand Thoroughbred Racing reacted swiftly, postponing Tuesday’s scheduled trials at the Te Awamutu track and announcing a suite of enhanced biosecurity protocols. All horses intending to race or attend a trial must now have their temperatures recorded for five consecutive days leading up to the event, including the morning of the competition. Any reading above 38.5 °C disqualifies the horse from participation until successive normal temperatures are documented. For horses originating from the Waikato zone, an additional requirement is a blood test (serology or PCR) performed within 48 hours of the event, coupled with a signed health declaration attesting to the absence of fever and negative test results. These measures aim to detect subclinical cases before they enter the high‑density environment of a race meeting.
Temperature Testing and Health Declarations
The five‑day temperature regimen represents a precautionary buffer designed to catch intermittent fevers that might be missed with a single‑day check. Trainers and owners are supplied with digital thermometers and instructed to log readings twice daily—morning and evening—to capture diurnal variations. The accompanying health declaration is a standardized form that must be completed by the horse’s owner or authorized agent, confirming that: (1) no temperature spikes above 38.5 °C occurred during the monitoring window; (2) the horse has not been in contact with known Strangles‑exposed to symptomatic animals; and (3), for Waikato‑based horses, a recent blood test returned negative for S. equi. Submission of the declaration is mandatory before a horse is cleared to enter the paddock or starting gate.
Industry Response and Transport Restrictions
Recognizing that movement of horses amplifies disease risk, a coalition of thoroughbred industry groups—including breeders, trainers, transport operators, and racing clubs—has voluntarily agreed to suspend the intra‑regional transport of horses from non‑affected areas into Waikato and Auckland while the outbreak remains active. Transport companies have reinforced their protocols, implementing vehicle disinfection between loads, requiring drivers to wear personal protective equipment, and maintaining detailed manifests to enable rapid trace‑back if a case emerges. Veterinary Association spokesperson Dr. Holly Blue emphasized that this cooperative approach is atypical but necessary given the disease’s propensity to spread through shared facilities and the high economic stakes involved in thoroughbred racing and breeding.
Export Concerns and Reputational Risks
Although Strangles is not a notifiable disease in New Zealand, the situation has raised alarm among exporters because Australia—the nation’s principal market for thoroughbred sales and live horse shipments—classifies Strangles as a notifiable condition and enforces stringent pre‑export testing and quarantine requirements. A prolonged outbreak could lead to heightened scrutiny from Australian biosecurity authorities, potential delays or refusals at the border, and ultimately a loss of confidence in New Zealand‑sourced bloodstock. Industry leaders are therefore engaging with the Ministry for Primary Industries and their Australian counterparts to clarify export‑health certification standards, explore the feasibility of pre‑export quarantine facilities, and develop contingency plans that safeguard both domestic competition and international trade.
Outlook and Next Steps
The immediate focus remains containment: continued isolation of affected premises, rigorous testing, and adherence to the new racing protocols. Veterinary authorities are conducting daily surveillance visits, and any new positives trigger rapid response teams to disinfect premises, trace contacts, and advise owners on treatment and quarantine durations. Longer‑term strategies under discussion include improving biosecurity education across the thoroughbred sector, evaluating the role of vaccination in high‑risk populations, and establishing a formal reporting mechanism for Strangles that would enable faster detection of future clusters. If the current measures succeed in curtailing transmission within the next few weeks, the industry anticipates a gradual return to normal racing schedules, albeit with heightened awareness of infectious disease risks that may shape future policy decisions.