Over the past several years work has been directed at better understanding this disease problem in horses along with how to treat the problem. One side of the body may be affected, but not the other. A strong, healthy immune system will help protect horses from contracting EPM. We have no data showing that the overall attack rate for EPM---the percentage of horses infected with S. neurona that develop EPM---in young performance horses receiving a preventive dose is lower that in untreated horses, [but] you need to remember that the overall … Sarcocystis neurona, the protozoal parasite that is the most common cause of the disease, is believed to pass from certain types of birds to opossums.Horses can become infected by consuming feedstuffs contaminated with opossum feces. The horses I see with severe symptoms are usually very weak, stressed or old. It is important to help the horse rebuild the immune system while treatment is ongoing. There are 2 ways to protect a horse—with vaccination, and limiting exposure to the protozoa (Sarcocystis neurona) by keeping feed and water from being contaminated by opossum feces. THE VACCINE – … Prevent EPM with a strong immune system. As with any disease, prevention is worth a pound of cure. Treatment is usually with drugs known to kill or retard the reproduction of the protozoa S. neurona. Trap and remove opossums to distant locations. Sarcocystis neurona, the protozoal parasite that is the most common cause of the disease, is believed to pass from certain types of birds to opossums.Horses can become infected by consuming feedstuffs contaminated with opossum feces. The best way to reduce the risk of your horse contracting the disease is to minimize exposure to opossum feces. Equine protozoa myeloencephalitis (EPM) is an infection of the brain and spinal cord of horses by single-celled parasites known as protozoa which is carried by opossums. Since most horses exposed to EPM never develop the disease, the causes of reinfection are likely to be the dose of organism consumed, health of the horse’s immune system and digestive tract, and possibly an immune defect in highly susceptible horses. Equine protozoal myeloencephalitis (EPM) can cause devastating neurologic illness in horses. Conventional therapy relies on relatively non This serious disease can be difficult to diagnose because its signs often mimic other health problems in the horse and signs can range from mild to severe. Equine protozoal myeloenencephalitis (EPM) is one of the most important neurologic diseases in the horse and remains a problem for horses and their owners. Equine Protozoal Myelitis is a devastating illness. Since equine protozoal myeloencephalitis (EPM) can leave a horse neurologically damaged in spite of treatment, conscientious horsemen seek ways to prevent this devastating disease. EPM Equine Protozoa Myeloencephalitis Prevention Any horse that eats hay, grain, or grazes in a pasture is susceptible to getting EPM. EPM Prevention Summary. There is no way to prevent EPM as no vaccine exists. EPM affects different neurons throughout the neurological system and can result in dragging or spastic gaits. In fact, the incidence of EPM may be less than 1%. It is caused by a protozoal parasite whose eggs are shed in opossum feces. EPM Treatment For Horses EPM Prevention and EPM products are all in this area. The natural carrier is the opossum. How to prevent horses from getting Equine Protozoal Myeloencephalitis (EPM) from opossums Opossums can transmit Equine Protozoal Myeloencephalitis (EPM) to horses. There is no way to prevent EPM as no vaccine exists. More than 50 percent of all horses in the United States may have been exposed to the organism that causes EPM.