What Is Equine Infectious Anaemia (EIA)?
Equine Infectious Anaemia is a non-contagious disease that affects horses but not humans. It is transmitted by carriers like horse flies (Tabanids) from horse to horse but the virus can also be spread by contaminated blood products, needles or equipment. The incubation period is between 2-7 weeks, but can be longer.
What Are The Signs of EIA?
Clinical signs can be acute, chronic or mild and transitory and they can be overlooked. Affected horses present fever, depression, petechiation (red spots) on mucous membranes, weight loss and weakness. Blood analysis shows anaemia and thrombocytopenia and further investigations may reveal enlargement of the spleen, liver and abdominal lymph nodes. Although horses may remain clinically normal after showing symptoms, they will become carriers and reservoirs of the virus.
How Is EIA Diagnosed?
The diagnosis of EIA is confirmed by the presence of antibodies to the virus in the blood, using the Coggins Test twice, 90 days apart. The results may be negative in the first two weeks of infection but the antibodies can be detected by 45 days and rarely by 90 days of infection.
How Is EIA Treated?
There is no specific treatment for this disease. No vaccine is available or allowed. EIA is a notifiable disease meaning that any suspected cases must be notified to the authorities. The UK is free from EIA and the last outbreak was registered in 2012. Suspected horses will be tested and separated from other horses for at least 60 days after exposure. Positive tested animals will be euthanased. All exported horses must have been tested negative for EIA either 21 or 30 days prior to export.
How Can EIA Be Prevented?
You can prevent the infection by:
- Testing the horses that are coming from countries where the disease is present (Argentina, North and West of Europe)
- Using insect repellent
- Making sure that horses are free from disease prior to breeding and that blood, semen and milk products are certified
