Todayโs path rounds are on ๐๐ช๐ฎ๐ข๐ง๐ ๐ข๐ง๐๐๐๐ญ๐ข๐จ๐ฎ๐ฌ ๐๐ง๐๐ฆ๐ข๐!
๐๐ก๐๐ญ ๐ข๐ฌ ๐ข๐ญ?
๐๐ช๐ฎ๐ข๐ง๐ ๐ข๐ง๐๐๐๐ญ๐ข๐จ๐ฎ๐ฌ ๐๐ง๐๐ฆ๐ข๐ is a viral disease caused by a ๐ซ๐๐ญ๐ซ๐จ๐ฏ๐ข๐ซ๐ฎ๐ฌ. This disease is highly transmissible with no known treatment, and infected horses will carry the virus for the rest of their lives. Therefore, prevention of this disease is critical!
๐๐ก๐จ ๐ ๐๐ญ๐ฌ ๐ข๐ญ?
Any horse can get this disease!
๐๐ก๐๐ญ ๐๐๐ฎ๐ฌ๐๐ฌ ๐ข๐ญ?
As mentioned, this disease is caused by a retrovirus. An infected horse is not directly contagious to other horses under most circumstances, meaning it cannot spread the disease on its own. So, the virus uses blood-sucking insects to hitch a ride between hosts! When a biting fly or mosquito feeds on the infected horse, the virus contaminates its mouthparts, allowing it to enter another horse during the insectโs next feeding. Another way the virus can transfer to another horse is re-use of bloody medical equipment like needles, surgical instruments or dental tools.
๐๐ก๐ฒ ๐ข๐ฌ ๐ญ๐ก๐ข๐ฌ ๐ ๐ฉ๐ซ๐จ๐๐ฅ๐๐ฆ?
The virus primarily infects ๐ฆ๐๐๐ซ๐จ๐ฉ๐ก๐๐ ๐๐ฌ, which are the bodyโs main clean-up cell. This infection results in a widespread immune response to try and clear the invader. However, this immune response has consequences for the animalโs blood cells, primarily their ๐ฉ๐ฅ๐๐ญ๐๐ฅ๐๐ญ๐ฌ (clotting cells) and red blood cells. The immune system overreacts to them, causing their destruction. This leads to ๐ญ๐ก๐ซ๐จ๐ฆ๐๐จ๐๐ฒ๐ญ๐จ๐ฉ๐๐ง๐ข๐ (low platelets) and ๐๐ง๐๐ฆ๐ข๐ (low red blood cells). Horses experiencing these problems may spontaneously bleed due to their lack of platelets, and are extremely lethargic with an increased heart and respiratory rate as their body tries to compensate for the reduced oxygen capacity of the blood. In some cases, the immune system may also attack the blood vessel wall, causing leakage of fluid into the tissues. This results in ๐๐๐๐ฆ๐.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐๐ข๐๐ ๐ง๐จ๐ฌ๐๐?
EIA is diagnosed using ๐ฌ๐๐ซ๐จ๐ฅ๐จ๐ ๐ข๐ ๐ญ๐๐ฌ๐ญ๐ฌ, meaning a sample of blood from the horse is exposed to the virus. If there are antibodies against the virus in the blood, the horse may be considered positive. Other supplemental tests will then be used to confirm whether the horse is truly infected.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ญ๐ซ๐๐๐ญ๐๐?
As mentioned, there is no treatment for this disease, so prevention is key! Unfortunately, horses that test positive are a significant risk to their peers, so most governments mandate their euthanasia to prevent further spread of the disease. However, there are now some sanctuaries for infected horses available where they are kept at a great distance from any non-infected horse, allowing them to live out the rest of their days.
๐๐จ๐ฐ ๐ข๐ฌ ๐ข๐ญ ๐ฉ๐ซ๐๐ฏ๐๐ง๐ญ๐๐?
The mainstay of EIA prevention is the ๐๐จ๐ ๐ ๐ข๐ง๐ฌ ๐ญ๐๐ฌ๐ญ, the same serologic test used to identify positive animals. Any horses interacting with or mixing with other horses at shows, events, etc should be tested and confirmed negative. Disinfection of surgical equipment, using needles a single time only and diligent insect control are also important in preventing this disease.
๐๐ก๐จ๐ญ๐จ๐ฌ
1-4) A poor horse with EIA, demonstrating widespread edema. Edema in horses tends to accumulate on their ๐ฏ๐๐ง๐ญ๐ซ๐๐ฅ surface (stomach-side), as you can see in this horse. His ๐๐จ๐ง๐ฃ๐ฎ๐ง๐๐ญ๐ข๐ฏ๐ (membrane around the eye) is also extremely pale due to his anemia.
๐๐จ๐ฎ๐ซ๐๐๐ฌ
Timoney PJ. Equine Infectious Anemia. Merck Veterinary Manual 2020.
Photos 1-4 ยฉย Wikimedia Commons contributor Darreenvt licensed under CC Share-Alike 4.0 International.
