The Doctor of Philosophy Seminar and Examination of Lauren Helber

Biography

Lauren is a 4th year PhD student that works with Dr. Sharon Witonsky. From Richmond, Virginia, Lauren graduated from Sweet Briar College with a Bachelor of Science in 2020 and came to Virginia Tech to further her education in the field of equine infectious disease. As an avid animal lover, Lauren owns a cockapoo, Indy, and a chestnut thoroughbred, South. After graduation, Lauren will be moving to Baton Rouge Louisiana to attend veterinary school at Louisiana State University. 

Funded by

• Grayson Jockey-club
• Virginia-Maryland College of Veterinary Medicine Office of Research and Graduate Studies

Lay Language Abstract 

Equine protozoal myeloencephalitis (EPM) is a common neurologic disease in horses in North and South America caused by the parasite Sarcocystis neurona. This disease is carried by the North American opossum (Didelphis virginiana), and horses encounter S. neurona when eating or drinking food or water contaminated with opossum feces. Not all horses who encounter the parasite develop disease and are able to clear the parasite before disease occurs. In one study conducted in this dissertation, it was found that the immunohistochemistry (IHC) test was significantly better at detecting S. neurona than polymerase chain reaction (PCR). Additionally, horses with EPM were broken into two groups: acutely affected horses with neurologic signs <6 months and chronically affected horses with neurologic signs >6 months. The study found that horses chronically afflicted with EPM had more degenerative changes compared to acutely affected horses. In addition, 4 horses who had previously been treated for EPM had S. neurona in their central nervous system (CNS), suggesting the ability of the parasite to persist after EPM treatment and that persistence of S. neurona may cause greater degenerative changes in horses with long-term neurological signs. The final study in this dissertation examined the potential for an assay to be used to help differentiate EPM from other neurologic diseases such as cervical vertebral stenotic myelopathy (CVSM). By measuring sCD14 concentration in the serum and cerebral spinal fluid (CSF) of control, EPM horses, CVSM horses, and EPM+CVSM horses, significant differences were found between control and EPM horses, and EPM and CVSM horses. This finding indicates the potential for sCD14 to be used to help differentiate between these two devastating neurologic diseases. Th future directions include preliminary data that could lead for a potential protein vaccine capable of protecting horses from EPM disease. Overall, the results of these studies not only improve our knowledge of EPM, but also has the potential to improve equine health around the world. 

Presentations

• March 2024 Graduate symposium and BMVS symposium- Potential for a new supplemental diagnostic assay to identify horses with Equine Protozoal Myeloencephalitis (EPM) 
• October 2023 BMVS seminar- Potential for a new supplemental diagnostic assay to identify horses with Equine Protozoal Myeloencephalitis (EPM)
• June 2023 ACVIM conference- Potential for a new supplemental diagnostic assay to identify horses with Equine Protozoal Myeloencephalitis (EPM) & Persistence of Sarcocystis neurona and histologic lesions in horses with Equine Protozoal Myeloencephalitis (EPM) 
• October 2022 EPM Havemeyer Conference- Potential for a new supplemental diagnostic assay to identify horses with Equine Protozoal Myeloencephalitis (EPM) & Persistence of Sarcocystis neurona and histologic lesions in horses with Equine Protozoal Myeloencephalitis (EPM) 
• September 2022 BMVS seminar- Persistence of Sarcocystis neurona and histologic lesions in horses with Equine Protozoal Myeloencephalitis (EPM) 

Examination Graduate Committee

Major Advisor/Chair:

Sharon Witonsky, DVM, PhD, DACVIM
Associate Professor
Equine Field Service 

Graduate Advising Committee Members:

Tanya LeRoith, DVM, PhD, DACVP
Clinical professor
Anatomic pathology

Kurt Zimmerman, DVM, PhD, DACVP
Associate head for Faculty affairs
Pathology/informatics

Roger Ramirez-Barrios, DVM, MS, PhD
Clinical associate professor
Veterinary Parasitology