Download Equine Infectious Anaemia.

Equine Infectious Anaemia. (Swamp Fever)
What is the Cause?
The cause is a virus from the same family as HIV, therefore, the virus of EIA is also quite good at
evading the host’s immune system and infected horses remain infected (positive) for the rest of
their lives. They therefore, act as a potential source of infection.
How is it spread?
The virus is spread by biting flies, which take blood from an infected horse and transfer virus to
another horse, by biting it. The type of flies that can transfer sufficient quantities of blood to achieve
infection are not usually found in the U.K. but there was a well publicised out break in Ireland a
couple of years ago. Here there were two abnormal routes of spread, one is currently sub-judicae,
the other was thought to be due to an infected mare, coughing with a blood in her airway and thus
spreading virus in small airbourne drops of blood.
What are the signs in the horse?
The signs can be very variable, a lot of horse show no signs at all.
The signs that can be associated with infection are:
 Fever
 Loss of appetite
 Weight loss, and this can be severe in chronic cases
 Anaemia ( low red blood cell counts )
 Tiring and poor performance
 Sudden death
How do we prevent infection?
Testing horses that are imported to the country to keep positive horses out. Once a horse is
infected, it is infected for life. The most common test is a Coggins Test.
Because they are a danger to other horses, those that test positive on a Coggins test will be
destroyed. EIA is a notifiable disease, so a positive Coggins test or signs suspicious of the disease
have to be reported to DEFRA.