Hendra Virus (HeV)

What is Hendra Virus? 

HeV is a rare infectious disease of horses.  It is also a Zoonotic disease which means it is transmissible from animals (horses in this case) to humans.  This virus is initially transmitted to horses from fruit bats / flying foxes when horses come into contact with bat droppings or other secretions (eg. feed/water buckets under bat roosting trees).  Bats do not show symptoms of the disease but are carriers of the virus. Humans can become infected by coming into contact with infected horse bodily fluids such as urine, faeces, blood and nasal secretions.

 

Hendra virus and flying Foxes

Flying Foxes actively transmit virus between themselves, between contact and bodily secretions.  Actual prevalence or actual number of infected flying foxes is unknown.

Horse infection appears to be ‘spillover’ of virus from flying foxes from birthing fluids / placenta and faeces.  Horse infection has occurred in paddock situation where flying foxes are actively roosting or flying.  There is low to limited risk of transmission between horses in a paddock situation or stable situation, unless there is direct exposure of an infected horse to an non infected horse.  Horses at highest risk are those that have access to the flying foxes roosting area and coming into contact with their (bats) secretions in the feed or water trough.

Transmission to other horses or humans from infected horses is by close direct contact with bodily secretions such as : Urine, Faeces, Saliva, Respiratory secretions or blood and also by indirect contact with virus via inanimate objects that have been in contact with infected horses such as halters, bridles, feed buckets, leads, etc.

Hendra virus as a notifiable disease 

Hendra is by law a ‘notifiable’ disease.  The DPI must be notified when Hendra Virus is suspected.

Confirmatory Hendra Virus in a horse is generally handled by Biosecurity Queensland personnel.  Where further testing of other animals and people is carried out.  The property is generally quarantined until HeV is cleared.

 

 Incubation period in horses

Time from virus transmission / infection to showing clinical signs

  • Apparent incubation period : 5-16 days

Horses can excrete virus in respiratory secretions as early as 2 days from infection

Already have widespread infection at time of showing clinical signs and necropsy

Course of illness in fatally ill horses – 2 days from first clinical signs to death


Hendra as a ZOONOTIC DISEASE

Human infection occurs from exposure to exposed horses from close contact of live horses or at necropsy / autopsy

Case fatality rate in humans 57%  – 4 deaths from 7 known cases of human infection

Time from human exposure of a sick horse to illness in humans : 5 to 21 days

Symptoms

  •   an influenza-like illness : fever, cough, sore throat, headache and tiredness,
  •   encephalitis (inflammation of the brain) : headache, high fever, and drowsiness progressing to convulsions and/or coma and death.

 

What do I look for in my horse? 

There is a variety of symptoms that have been shown in horses with confirmatory Hendra virus.  These cases have generally shown rapid deterioration with depression, increased body temperature, increased heart rate and respiratory rate.  Some cases have actually initially been reported as colic – showing symptoms of weight shifting, depression and restlessness.  There are also signs of respiratory distress, nasal discharge and neurological signs such as a wobbly gait, inability to rise, muscle twitching, loss of vision and urinary incontinence.

 

If you see these symptoms

Call your veterinarian or Bioscurity Queensland 13 25 23. If you have been in contact with a sick horse have a shower and change your clothes. It is also important to stay away from other horses until advised further by your veterinarian or Biosecurity Queensland.

 

Contacts : if have concerns about HENDRA virus

  • Your local Vet
  • Qld DEEDI : www.dpi.qld.gov.au
  • Biosecurity Queensland on 13 25 23
  • Queensland Health 13 43 25 84
  • Emergency Animal Disease Watch Hotline on 1800 675 888 (24-hour hotline).
  • Workplace health and safety  1300 369 915

 

How to minimise the risk of HeV

  • Place feed and water containers under cover areas, not under trees which bats may be roosting.
  • Avoid feeding fruit/sweet feed such as molasses as this may be attractive to flying foxes
  • Remove horses from paddocks with flowering or fruit trees.
  • Keep any sick horses isolated from other horses
  • Minimise the handling of sick horses.
  • Wash hands with soap and water after handling horses
  • Disinfect any tack used by a sick horse.


Personal Protective Equipment or PPE is the equipment used to prevent any exposure to the virus. The most essential equipment is listed here and includes nitrile or latex gloves. We  (Gray st Vet Clinic) would double glove for any suspect Hendra horse.   P2 face masks are particulate respirators required for dealing with Hendra outbreaks. Normal surgical face masks will not filter out Hendra virus particles from the air. Goggles, gum boots and full length clothing will reduce the risk of much of the skin from coming into contact with potential hendra virus contaminated material. Always cover any cuts or abrasions with appropriate bandaging.

 

Equipment to protect from exposure to the virus

  • Latex/Nitrile gloves (double glove)
  • P2 face masks
  • Goggles
  • Gum boots
  • Full length clothing
  • Cover abrasions with bandaids/bandaging

Remove all disposable items such as gloves in place in garbage bags that can be tied up. With undisposable items such as boots and clothes you can either disinfect by washing in soaps or disinfectant such as dettol, washing detergent, domestos or iodine. Otherwise if unsure leave this equipment in cable tied bags until the result of the Hendra samples are returned and disinfect as appropriate.

  • Throw out disposable equipment (gloves) in tied up garbage bags
  • Wash clothes and boots etc with disinfectant or soap (Dettol, demestos, iodine) OR…
  • Leave in zip locked bags until Hendra sample results are returned.
  • Leave P2 mask on until completely free of ‘dirty’ equipment.

 

HeV is a relatively new virus and there is still much to learn about this virus. A vaccine for horses has been developed but is still in the testing phases and is not yet available. This virus causes a life threatening condition in humans therefore personal safety for yourself and others the utmost important. Caution should be taken when handling any sick horse.

 

TAKE HOME MESSAGES

Emerald has not yet had a known case of Hendra virus but the risk is there so EVERYONE needs to be aware.

Relatively new disease : studies and research is still being carried out – TAKE NO RISKS

  • Reduce the possible exposure
  • Use PPE with sick animals
  • Use proper hygiene practices between horses and jobs
  • Consider other people’s safety
  • If not sure – get another opinion – CALL the VET!

Human safety is of the utmost importance when dealing with any case of a ‘sick horse’ therefore :

  • Be prepared to answer some questions on the phone by the veterinary nurse regarding – history of the horse movements, location of property and known flying fox habitats, horse symptoms, etc
  • Don’t freak out when your vet attends the consult in full protective wear as seen in pictures on the web

 

Further Hendra VIRUS information available from:

www.emeraldvet.com

Gray St Veterinary clinic WEBSITE

Follow our immediate posts and updates on facebook and website

http://www.dpi.qld.gov.au/4790_2900.htm

Subscribe online or call 13 25 23 for your Biosecurity QLD Hendra virus information pack

www.qldhorsecouncil.com

Queensland horse council website

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