Pathogenes Inc.
Pathogenes Inc.
PO Box 970, Fairfield, Fl. 32634
15471 NW 112th Ave, Reddick, Fl. 32686
ph: 352-591-3221
fax: 352-591-4318
sellison
Pathogenesis of EPM
Parasites to Paresis...
Equine protozoal myeloencephalitis is a devastating disease caused by Sarcocystis neurona in horses. Our goals are to prevent disease and find effective treatments for those horses that have EPM.
Basic to establishing effective treatment therapies was the ability to identify active disease and understand how the parasite infects horses as well as how the horse responds to infection.
Most of the cases of EPM that are diagnosed in the field are recognized as chronic infections. These chronically infected horses have infections lasting for a month or more. In our studies animals that were infected with S. neurona showed obvious signs that could be recognized early in the disease.
Our research horses are selected based on a normal neurological exam, normal physical exam, normal levels of serum vitamin E, normal cervical spinal (neck) radiographs, no serological evidence of EPM, EHV-1, or other infections. We use board certified neurologists (that are skilled in diagnosing EPM) to examine our horses without knowledge of infection, treatment, or therapies. During the rehabilitation period after a trial we test therapies that are commonly used to treat EPM. This has given us a unique perspective on acute and chronic disease and the progression of disease in many individual animals.
To read a discussion on the pathogenesis of S. neurona in horses please go to www.pathogenes/blog and look for the disease related blogs.
We know a great deal about the disease EPM in horses, however, there are some interesting things that we do not understand. Most horses succumb to EPM if they are challenged experimentally. The disease follows a typical progression that starts at 15 days and manifests from 30-45 days, but there are a few exceptions. Rarely (0.01%), a horse shows few signs until displaying fulminant disease from 90-100 days.
Field cases of EPM have been diagnosed when the horse had no possible exposure to S. neurona for years. These observations indicate that this latent infection may be present, but rare, in both natural and experimentally infected horses. Antibodies against S. neurona were detectable in these latent infections. In our latent cases, there was a dramatic rise in antibody titer preceeding the onset of acute EPM.
EPM scores are helpful to evaluate horses
We found the daily score correlated well with severity of disease and outcome when consecutive multiple exams were recorded. While daily score is not applicable to the rare (0.01%) latent infections, when coupled with a dramatic rise in antibody titer disease, could be predicted.
Pathogenes Inc.
PO Box 970, Fairfield, Fl. 32634
15471 NW 112th Ave, Reddick, Fl. 32686
ph: 352-591-3221
fax: 352-591-4318
sellison
