New Hendra Policy For Equine Clients of Gray Street Veterinary Clinic

Policy on Hendra Virus and Vaccination


“Comes in to effect on 1st of February 2015”


Hendra virus is a fatal disease in horses and in humans.  Mortality rate in horses known to have contracted Hendra virus is 100%. The mortality rate in humans is 60%. Veterinarians and their staff are the most at risk of contracting Hendra virus and they account for all but one of the human cases.

There is a large range of clinical signs possible in horses that have contracted Hendra virus.  Horses with Hendra virus have been variously diagnosed with colic, snake-bite, “choke”, have been tangled in fencing wire, stuck in dams or have been vaguely unwell.  Infected horses have had a normal, high or low temperature.   In recent cases there has been no known activity of flying foxes.

It is not possible to diagnose Hendra virus without an exclusion test from Biosecurity Queensland. This requires sending samples to Brisbane with results taking between two and five days.

The practical consequences of not vaccinating your horse are many but there are several important repercussions:

  1. There is a known and serious risk of injury or death because of this virus.  Although infection is not common, the consequences are very serious including death of horses and people. Hendra virus is categorised as a “BSL-4” virus (Bio-safety Level 4 – the same as Ebola Virus) and is considered by NAID and CDC to be a Category 3 bioterrorism agent or pathogen.
  2. Any horse that is unwell must also be considered at risk of having Hendra virus (as the clinical signs are so variable). Therefore an unvaccinated horse cannot have invasive treatments, until a negative exclusion test can be performed.  This usually takes between two and five days.  This time frame may dangerously limit treatment options for seriously unwell horses.
  3. As of December 1st 2014 our closest referral equine specialist clinic (Townsville Veterinary Clinic) will no longer be accepting non-vaccinated horses for referral of any kind.

Hendra vaccination is considered to be safe and effective.  The vaccine has been available for two years and in that time over 100, 000 horses have now been vaccinated and the rate of complications is very low. The most common complication is a swelling at the injection site, or very rarely a raised temperature or malaise (off food) for 24 hours.  No deaths or serious injury have been reported after Hendra virus vaccination. There are no known repercussions for reproductive animals.

From February 1st 2015 Gray Street Vet Clinic will use the following guidelines for seeing unvaccinated horses:

  1. Routine invasive examinations on well, unvaccinated horses will not be performed unless Hendra virus vaccination is performed prior to the routine examination or treatment. Exceptions may be made base on a risk assessment by the vet involved.
  2. Sick, unvaccinated horses will still be seen, though not at the hospital. An exclusion test will be required before admission to our hospital (24 – 48hrs). Owners may also be charged for the costs of an exclusion test (packaging and shipping of the sample to Brisbane). Treatments will be limited to those that are deemed safe based on a risk assessment by the attending veterinarian. Please note that this could mean that your horse may receive sub-optimal treatment if it is not vaccinated.
  3. Sickunvaccinated horses presented for emergencies may require exclusion testing prior to any invasive or risk associated treatment being provided.
  4. Admission of routine, non-invasive cases to the clinic for day procedures (bandage changes, eye problems, lameness examinations, x-rays) will still be allowed to be performed at the clinic or farm however we do still recommend vaccination. Again, treatments given will be non-invasive.
  5. Any horse boarding at the Gray Street Clinic for more than the day will be required to be vaccinated.
  6. Any horses boarding at the Central Queensland Breeding Center are required to be Hendra vaccinated.

Gray Street Veterinary Clinic has an obligation to its clients and staff to protect and advise them on the best way of preventing disease in horses and people. Vaccination is the best way of preventing Hendra virus infection in horses and people.