Horse vaccination schedule (Australia): the 2-in-1, Hendra, and why there is no flu booster

By Sebastien Kister

Last reviewed 12 October 2026

Read a British or American vaccination guide and most of it is about influenza: which booster interval, which rulebook, which deadline. None of that applies here. Australia has no flu vaccination at all, and the question that takes its place is Hendra, a virus that kills horses and has killed people, and whose vaccine decides as much about your vet's visit as about your horse.

No flu vaccine, on purpose

Equine influenza reached Australia in August 2007, in New South Wales, and the outbreak was eradicated; the country declared itself free of the disease again in 2008. Since then the vaccine has not been approved for use here, precisely because the disease is gone. A horse being exported can be given a permit to be vaccinated, and that is the only routine exception.

That matters if you compete internationally. The FEI's 2026 Veterinary Regulations make flu vaccination mandatory, but allow an exception where national legislation prevents the vaccine, and only for horses competing in that country. The FEI's own HorseApp vaccination module states that its recording requirement does not apply to Australia, New Zealand and Indonesia. A horse leaving to compete overseas has to be vaccinated and recorded like any other, which means starting the course, under permit, well before it travels.

What is on the list instead

The University of Melbourne's equine prescribing guidelines list the vaccines available for horses in Australia as tetanus, strangles, Hendra virus, equine herpesvirus 1 and 4, Salmonella and rotavirus. In practice they sort into three groups:

The Melbourne guidelines are candid that vaccination may reduce the severity of disease rather than prevent it, which is why New South Wales biosecurity advice pairs it with isolating new arrivals for at least 14 days. Tetanus has a wrinkle of its own: Zoetis notes that the Equine Infectious Diseases Advisory Board recommends a tetanus booster every 12 months, while the older tetanus-only label allowed much longer gaps once a horse had been boosted, a figure a 2024 review traced back to studies from the 1970s and 80s. Your vet will tell you which they follow; what you need is the date of the last dose.

Hendra: the vaccine that decides whether the vet comes

Hendra virus lives in flying foxes and spills over into horses, and occasionally from horses into people. Since it was identified in 1994 it has killed more than 100 horses, every one of them in Queensland or New South Wales. Seven people have been infected and four have died, all in Queensland, the last in 2009. It has not gone away: an unvaccinated horse near Newcastle was confirmed in July 2023, an unvaccinated horse in south-east Queensland died in July 2025, the state's first case since 2022, and in December 2025 the Northern Territory confirmed its first detection of the virus in a bat. A variant found in 2021 is covered by the same vaccine, according to the New South Wales department.

The vaccine, Equivac HeV, has been fully registered since August 2015. It runs to its own rules:

• Only a vet can give it, and every dose is entered in a central database.
• The horse must be microchipped before the first dose, so the record is tied to a horse rather than a description.
• The course is three doses before it settles into a year: two doses three to six weeks apart from four months of age, a third six months after the second, then a booster every 12 months. Foals of vaccinated mares usually start at six months.

Vaccination is not compulsory in Queensland or New South Wales. What makes it more than a personal choice is the vet's side of it. The Australian Veterinary Association's policy notes that vets and other horse businesses have legal obligations to keep a safe workplace, and that some practices judge the risk of examining unvaccinated horses to be too high. A sick, unvaccinated horse may get a slower, more cautious examination, or a practice that will not come at all, until Hendra is ruled out. The vaccination record is, quite literally, part of the call.

Nobody national requires it, but some gates do

There is no federation rule to point to. Equestrian Australia introduced a Hendra vaccination by-law in 2014 and revoked it on 2 February 2015, and since then has had no national policy, encouraging event organisers to assess their own biosecurity risk instead. Racing in Queensland urges vaccination without mandating it.

Individual venues are another matter. The Royal Queensland Show's exhibitor information requires every horse entering the Brisbane Showgrounds to be Hendra vaccinated, and in 2018 its harness racing entries had to be current on the vaccine registry by a set date. The practical rule is to read each event's entry conditions rather than assume, and to have the vet's certificate where you can find it.

Tetanus: the date nobody remembers until the horse is cut

Tetanus spores live in soil, and a horse is one of the most susceptible animals there is. When an injured horse's tetanus status is unknown, the vet gives tetanus antitoxin, which protects for about three weeks, alongside a first dose of vaccine, and the course has to be completed afterwards. A horse whose last dose you can actually date does not need any of that. It is the cheapest record in the stable to keep, and the one most often reconstructed from guesswork.

Why the calendar drifts

An Australian horse can easily be on three clocks at once: a 2-in-1 that comes due every year, a Hendra course that steps from three weeks to six months to twelve, and, for a breeding mare, an EHV booster every six months plus doses timed to the pregnancy. Each one counts from when the last dose actually went in, not from when it was planned, and every late visit shifts every date after it.

The Hendra registry knows when your horse was vaccinated; it does not send you the next date. And when someone asks, at the gate or on the phone at 6 a.m. with a sick horse, they need the answer now, not after a call to the clinic.

Sources

• WA Department of Primary Industries and Regional Development — Equine influenza (vaccine not approved in Australia; permit for export)
• World Organisation for Animal Health — Australia's self-declaration of freedom from equine influenza
• FEI — 2026 Veterinary Regulations and FEI HorseApp vaccination module
• University of Melbourne — Australian Veterinary Prescribing Guidelines, equine immunisation
• Zoetis Australia product information: Equivac 2in1, Equivac HeV, Duvaxyn EHV 1,4
• New Zealand Veterinary Journal (2024) — tetanus prevention guidelines for horses (label intervals; antitoxin)
• NSW DPIRD — Biosecurity for horse owners (isolating new arrivals)
• Australian Government DAFF — Hendra virus and Queensland Health — Hendra virus
• Queensland Government — Summary of Hendra virus incidents in horses, NSW DPI — Hendra confirmed near Newcastle (2023) and NT DAF — First NT detection of Hendra virus in a bat (2025)
• NSW DPI — Hendra virus and vaccine information for vets (schedule; the 2021 variant)
• Zoetis — Hendra virus vaccine fully registered (2015)
• Australian Veterinary Association — Hendra virus policy
• Equestrian Australia — Hendra and Queensland Racing Integrity Commission — Hendra virus
• Royal Queensland Show (Ekka) — horse exhibitor information

Labels, policies and event conditions are revised; check the current version before relying on it, and confirm the program with your vet.

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