Vaccine Helps Treat Pythiosis

The Horse recently discussed pythiosis in the aftermath of hurricanes. In 1994, Michigan State University (MSU) researchers teamed with scientists at Pan American Veterinary Laboratories (PAVL) to complete development of an immunotherapeutic vaccine to help treat pythiosis (Pythium insidiosum) in dogs and horses. In 1999, Leonel Mendoza, PhD, an associate professor at MSU, patented the vaccine, and four years later, PAVL licensed the marketing rights to it. The USDA granted a drug license for the vaccine in early 2004, making it commercially available in the United States.

Mendoza explains, "Equine pythiosis is characterized by the development of cutaneous, subcutaneous, lymphatic vessel, intestinal, (and) granulomatous lesions, and less frequently by the involvement of bones and lungs (chronic pythiosis). Lesions caused by P. insidiosum can occur on any part of the horse's body, but are more common on the lower limbs because they first come in contact with the organism in infested environments (stagnant water, grasses, etc.)." If the disease is not treated in the early stages, it is 100% fatal.

The vaccine is given in three subcutaneous injections, and Mendoza says it has an efficacy rate of 75%.

About the Author

Chad Mendell

Chad Mendell is the former Managing Editor for .

Stay on top of the most recent Horse Health news with FREE weekly newsletters from Learn More