Hendra Vaccination - THE FACTS

By: David K Lovell BVSc MACVSc - Redlands Veterinary Clinic

Vaccination against Hendra Virus has been available for some time now and it offers horse owners the opportunity to safeguard their horses, themselves, their family and all the people who come in contact with their horse.

Yes, the disease is extremely rare and the chances of you being the next unlucky one to experience the disease are very low, BUT, what if? 

There certainly are a lot of very grave misconceptions out there regarding the Hendra vaccinations.

Yes, the Hendra vaccine is not yet registered for “open” use on horses. Arrival at that status will still take some considerable time, probably even yet another year or so.

The only reason that the vaccine has been released as it has been is because of emotive and constant demands by the horse industry for the authorities “to do something” to protect horses and humans from dying due to Hendra infection. I find it mind boggling, and very, very disappointing to see and hear the current outcry that has been going on since the vaccine was released. Yes, it has been released under “special permit”, only because of the pressure that was being placed on “governments” to do something. To do otherwise would mean a delay of possibly 3 – 5 years before final approval and registration could be achieved. How many more horses and people would die before that happened?

A very large amount of testing has in fact been done up to this point. What is known, is that the vaccine is extremely effective. It provides a very, very high level of immunity and protection. Also, it is known that the vaccine is extremely safe. Over 100,000doses have now been used and there have been reports of possibly a maximum of 150 instances of some reaction, and those have only been minor local reactions at the injection site. Who could possibly object?

The only issue with breeding animals is that the trials have not been completed. The very nature of having to trail the dose on pregnant animals means that it will take many years to complete. That is all that it means. Before it can be approved officially and registered for breeding animals, the work has to be done. There would be absolutely no adverse effects on breeding as such. The only possible scenario for trouble could be giving the vaccine to a heavily pregnant mare. Every heavily pregnant mare has to be treated with caution as they are so prone to miscarriage. The reality is that any managerial procedure should be avoided, if possible, in this category of horse.

Let’s get down to tin tacks. The objection to the vaccine is cost, not concerns about perceived problems. Yes it is a cost, and a not inconsiderable cost particularly for owners with larger numbers of horses. Production and development of any drug or vaccine involves an enormous outlay by the developers. Who is supposed to pay? Surely the end user. It would appear that the horse owning public had expected the “government” to bear the cost. For what possible reason? No one could expect the pensioner in a retirement village, the unit dweller in the city, or any of the millions of tax paying citizens out there, who have nothing to do with horses, to subsidise the pleasure activities of the relatively small numbers in the population who choose to own horses.

As you well know, a horse is an extremely expensive commodity to own or be paying up for. This is another cost, but the reality is that the cost of the vaccine, relative to all the other expenses involved in horse ownership, is only a small component. More to the point, what is the cost of not vaccinating? Your beloved horse dying, yourself dying, or worst of all, someone that you know, coming in contact with your horse, contracting the disease and dying. It can only be regarded as irresponsible for anyone choosing to own a horse, not to have it vaccinated.

Thankfully there is now an extremely effective mechanism for protecting horses and people for Hendra virus. The logical evolution in the soon to be foreseeable future, is that it will come to be regarded as negligence for a horse owner not to utilise available technology to protect themselves and those people around them, from the possibility of Hendra disease. This will apply in particular to employers involved in the horse industry. Workplace Health and Safety will dictate that all workers need to be protected.

This, in fact, has been a major driver prompting the Queensland Racing Board, and Equestrian NSW, to have now mandated vaccination. Queensland Racing suggested that “there are approximately 30,000 workers involved in the industry, it is imperative that their interests and welfare be taken care of”.

I cannot speak for the RNA as to the reasons for their decision to make vaccination compulsory, however, it would appear very logical that public liability would be very high on the list that may have been behind their thinking.

Of all the horse events and functions, the Brisbane Show would have to be one that would be in the higher risk category. At this show, many horses are stabled on the grounds for an extended period of time, (up to 2 weeks). The incubation period for Hendra disease in the horse is known to be up to 16 days, therefore a horse could be perfectly normal when brought to the precinct, but may have contacted a bat in the days or weeks prior to coming, and not become ill until having been on the grounds for some time. Imagine the fiasco. Hundreds of horses quarantined in those stables at the exhibition. That alone would be an unthinkable disaster, not to mention the horror of some human contracting the disease.

The decision by the RNA was a so called “no brainer”. In my opinion, they would be negligent not to insist that the now available unbelievably effective means of protection, not be a requirement. The horse industry should be lauding and congratulating them for their foresight, not whinging about the couple of hundred dollars that people who choose to own an already extremely expensive commodity, have to pay for protection.

Rest assured, this form of thinking among event organisers, service providers, and anyone that has anything to do with the horse industry, will become the norm.

I could go on forever. What I have tried to give you above are some general perceptions, and hopefully valid reasons as to why vaccination of horses against Hendra disease is essential. My comments are not meant to be specific or related to anyone in particular. I am merely attempting to “get a message across”.