|The transmission of the virus
that causes equine infectious anemia has been known since the year 1904. It was
then linked to pests which live on the lifeblood of the horses. Perhaps the most
common culprit is the horsefly. Known as a large insect with a painful bite, a
horse plagued by these pests will use its tail and twitching movements to
interrupt the fly from completing its meal and sending it on its way. If a
horsefly has been feeding on a horse infected with EIA and is then scared off,
it will probably fly to another horse to complete its feeding. At that time it
will also transmit the virus that causes EIA to the other horse.
You may be able to tell if your horse is affected by any one of the three forms
of clinical EIA:
- During the early presentation of the disease the horse
will be feverish and somewhat uncoordinated. A horse may show these kinds of
symptoms for a number of days. This is incidentally also the most likely phase
of transmission to another horse.
- Following the initial phase you will be able to notice a sudden loss of
weight, more fever, and an overall display of weakness. This will also be the
stage at which a veterinarian will be able to diagnose anemia. Pregnant mares
will most likely abort their foals.
- The third and final stage of the condition will see the horse returning to
normal, yet it will be a lifelong carrier of the disease. In addition to the
foregoing, these horses are very likely to be more susceptible to illness and
stress related conditions.
Sadly, many horses will die during the first two stages. This condition is so
common, that is has been known to run rampant on breeding farms and even race
tracks, resulting in the losses of many animals. Since the illness so highly
contagious, new horses should always be quarantined until a blood test checking
for antibodies can be performed, and hopefully yield negative results.