Equine Infectious Anemia (Coggins’ Disease)

Ashley Griffin, University of Kentucky

Equine infectious anemia (EIA), or swamp fever, is a viral disease that occurs worldwide. The disease is usually spread by horse flies biting an infected horse, then biting a healthy horse. The disease can also be transmitted by the use of nonsterile needles and blood-contaminated surgical instruments.

Clinical Signs


1. high fever
2. labored breathing
3. pounding heartbeat and exhaustion
4. anemia.


Horses that recover usually remain carriers of the disease. The death rate is low.…

Equine Protozoal Myeloencephalitis (EPM)

Craig Wood, University of Kentucky

The organism Sarcocystis neurona, a single-celled animal, can cause equine protozoal myeloencephalitis (EPM), a neurological disease that can affect equines of any age, sex, and in any location throughout the United States. The parasitic cycle involves birds eating plants and other animals of prey that carry the sporocysts of the organism. The opossum then eats birds killed by the effects of the disease. The organism reproduces sexually in the opossum and is passed …

West Nile Virus in Horses

West Nile Virus (WNV) is a mosquito-born virus that can cause encephalitis (inflammation of the brain) or meningitis (inflammation of the lining of the brain and spinal cord) in humans and horses. Mosquitoes that acquire it from infected birds transmit the virus. This virus was first discovered in the United States in New York in 1999 and has quickly spread throughout the U.S. The virus was found in dead birds as far west as Missouri and eastern Iowa in the …

Disease: Equine Influenza

Equine Influenza is a highly contagious respiratory disease, which spreads rapidly among susceptible horses. It is rarely fatal except in young horses. The incubation period of influenza is ~1-3 days. Clinical signs begin abruptly and include high fever (up to 106 degrees F [41.1 degrees C]), serous nasal discharge, and coughing that is dry, harsh, and nonproductive. Depression, anorexia, and weakness are frequently observed. Clinical signs usually last less than three days in uncomplicated cases. Cough develops early in the …

Equine Viral Rhinopneumonitis in horses

Ashley Griffin, University of Kentucky

Equine viral rhinopneumonitis (EVR) produces an acute respiratory catarrh, which is inflammation due to excessive discharge or buildup of mucus in the throat and nose. The Type I strain of EVR is the most common virus found in horses. Transmission of EVR occurs with direct or indirect contact with virus-laden nasal discharge, aborted fetus, or placenta. 

Clinical Signs


1. congestion and clear nasal discharge
2. mild to server ataxia or paresis (slight of incomplete paralysis) of …