Why Hendra Virus is different to Equine Influenza

Why Hendra Virus is different to Equine Influenza

11 July 2011

Hendra virus facts and why it’s different to Equine Influenza (EI) by Wendy Cohen.

The recent cases of Hendra virus in Queensland and NSW have generated concern for everyone associated with the horse industry. It’s important for everyone to understand the basics, and how to protect themselves and their horses from Hendra virus, and also to understand how and why this disease is different to EI.

The basics

Hendra virus can occasionally spread from flying foxes to horses. This is an unusual event, and the circumstances that allow the spread from flying fox to horse are not fully understood. Once a horse becomes affected with Hendra, the death rate is very high. Clinical signs are VARIABLE and can include high temperature, depression, nasal discharge, problems breathing and in-coordination. The horses rapidly deteriorate within a short period of time  (few days).  Hendra virus is not very contagious, and it requires very close contact between a Hendra affected horse and a healthy horse, or a Hendra affected horse and a human, for the virus to be transferred. If a human contracts Hendra virus, it is most likely that they will become very sick, and death is a real possibility, even with treatment.

Horse movements

Because Hendra is not highly contagious, it does not spread from farm to farm. Although it is extremely concerning that there has been a cluster of Hendra positive horses in the last 2 weeks, there is no evidence to suggest Hendra is spreading from farm to farm; all of these cases are isolated events.

This is completely different from Equine Influenza (EI), which is a highly contagious disease. EI spreads rapidly from horse to horse and farm to farm. This is why it was necessary in 2007 to halt horse movement across NSW and Queensland to try to contain the spread of EI. EI has been eradicated from Australia and is a completely different virus to Hendra.

Because Hendra is not very contagious, there is no need to halt horse movement in NSW or Queensland. EVA understands that there are no plans to restrict horse movement, other than on quarantined farms.

There is a Hendra horse vaccine being developed but it will not be ready for release until 2012 or 2013. Contact your veterinarian quickly if your horse appears ill, and limit contact with sick horses until a veterinarian can assess the horse.

12 Simple Steps to minimise the risk of Hendra for yourself and your horse

(Reproduced with the permission of Dr David Lovell, B.V.Sc., M.A.C.V.SC., Q.D.A.H., G.C.M. Redlands Vet Clinic, Qld)

  1. WEAR DISPOSABLE GLOVES. Always have a box of disposable gloves on hand. Wear them if doing anything with a horse that involves contact with horse body fluids. THIS IS IMPORTANT.
  2. WEAR Personal Protective Equipment (PPE) IF IN ANY DOUBT. Do not, in any circumstances, approach or attempt to do anything potentially invasive with any suspect horse without adequate PPE. Leave it to the Experts.
  3. WASH YOUR HANDS AND EQUIPMENT. A most important factor. Strict personal hygiene is the key component in avoiding infection. Wash hands and equipment and use disinfectant.
  4. TPR YOUR HORSE DAILY. Any deviation in the horse’s temperature, heart rate, or respiration is something all owners’ should know and is a primary indicator of the horse’s health.
  5. CLINICALLY ASSESS YOUR HORSE. Owners know their horse and intuitively will pick when the horse is not himself. Investigate thoroughly any changes in signs, symptoms or behaviour.
  6. RISK ANALYSIS. Always assess the situation and circumstances surrounding yourself and your horse and make a judgement as to the possible risk of a problem.
  7. MAINTAIN A “PERIMETER” AROUND YOUR PROPERTY. Maintain a perimeter so that horses across the fence cannot contact each other.
  8. “QUARANTINE” ANY NEW HORSES. A critical issue. Remember the incubation period (5-16 days) where an infected horse can appear normal. Isolate any new horses that arrive at your property.
  9. STABLE HORSES or HOLD in “SAFE” YARDS at NIGHT if possible when flying foxes are most active.
  10. IDENTIFY ALL PLANTS AND TREES. Know whether the trees on your property are food sources for flying foxes.
  11. ELIMINATE FLYING FOX FOOD SOURCES. If you cannot remove dangerous plants or trees, at least fence them off or prevent your horse having any access. Make sure that food sources attractive to flying foxes such as fruit and vegetables are not left around horses.
  12. FEED & WATER HORSES IN OPEN SPACES or INDOORS. Do not feed or water horses near any possible site where Flying Foxes may feed, roost, or perch

More information at Australian Veterinary Association website: www.ava.com.au

Qld Dept Primary Industry website: www.dpi.qld.gov.au/4790_2900.htm

Queensland Health website: www.health.qld.gov.au