Two women in green shirts stand beside a brown horse in a stable. One, likely a veterinarian, holds the horse’s halter while the other appears to be examining the horse’s mouth. Light filters through the ceiling above.

Coggins Test: What It Is and Why It Matters

The Coggins test is a critical blood test for horses to detect Equine Infectious Anemia (EIA), a serious and potentially fatal viral disease.

Two women in green shirts stand beside a brown horse in a stable. One, likely a veterinarian, holds the horse’s halter while the other appears to be examining the horse’s mouth. Light filters through the ceiling above.
Two women stand with a brown horse in a stable. One, wearing a maroon shirt, holds the horse's lead while the other, possibly a veterinarian in blue, appears to be examining or treating the horse's side.

What is Equine Infectious Anemia (EIA)?

EIA is a contagious disease transmitted by biting insects like horseflies and deer flies. It weakens the immune system, leaving horses susceptible to infections and other health problems.

A brown horse stands on green grass near a wooden fence under a blue sky with scattered clouds, close to a veterinarian clinic, with trees and a distant building in the background.

What Happens if the Test is Positive?

A positive Coggins test result indicates that the horse has been exposed to the EIA virus.

  • Important Note: A positive result does not always mean the horse is actively sick.
  • Further Testing: If the initial test is positive, further testing is required to confirm the diagnosis.
  • Quarantine: Infected horses must be isolated to prevent the spread of the disease.

A brown horse stands in a grassy field as a white horse grazes nearby under a clear blue sky, perfect for a Vet or Animal Hospital promotional photo.

How Does the Coggins Test Work?

The test detects antibodies in the horse’s blood that the immune system produces in response to the EIA virus.

A brown horse stands in a grassy field as a white horse grazes nearby under a clear blue sky, perfect for a Vet or Animal Hospital promotional photo.