How does my horse get infected with the
equine arteritis virus?
EAV infection can be
transmitted among horses in four different ways: via respiratory
secretions from acutely infected horses, in the semen of infected
stallions to mares, indirectly through contaminated tack/equipment
shared between horses, and occasionally from an infected pregnant mare
to her unborn foal.
What are the signs of equine viral
majority of horses that become infected
with the virus show no
signs of illness! Horses that are suffering from equine
viral arteritis present with general signs of illness including
(near 40.5 degree celcius) for 1-5 days,
anorexia, depression, serous nasal discharge, lacrimation (tearing),
coughing, edema of
limbs, skin rash and swelling of eyelids. EVA can cause abortions
in pregnant mares, and can become a chronic
infection in breeding stallions.
How long will my horse be
The incubation period is 1 to 6 days, and clinical signs usually
persist for 3 to 8 days. Some horses may require a couple of
weeks to return to normal. As previously mentioned, recovery is
usually full and uneventful.
Can I vaccinate my horses
against the equine arteritis virus?
Yes, there is an effective vaccine licensed for use in horses in
Canada. Consult your veterinarian for more information.
Can I breed my mare to a
You can choose to breed to your mare to a carrier stallion. You
should ensure that your mare is vaccinated at least 3 weeks prior to
breeding. It is also recommended to isolate your mare for three
weeks after breeding to an EAV carrier stallion.
Is EVA a big concern for
horse owners in western Canada?
Equine viral arteritis is a disease the horse owners should be aware of
but not lose sleep over! Many horses infected with EAV don't
exhibit clinical signs. Those that do develop clinical signs
typically have an uneventful recovery. The biggest concern is for
those with pregnant mares. Owners should ensure that the
stallions they breed to (or have semen collected from) are EAV free,
and take proper precautions if they elect to breed to a carrier
stallion. It is important to differentiate disease caused by EAV
from other infectious agents such as equine herpes virus or Streptococcus equi (the causative
organism of strangles).
Gay, C.C., Hinchcliff, K.W., Radostits, O.M. (2007). Veterinary
Textbook of the diseases of cattle, sheep, pigs, goats, and horses.
Saunders Elsevier Company, Ltd. Toronto
Tenth edn. Pps. 1320-1322.