Kathryn Duncan, DVM, PhD, DACVM (Parasitology)

Dr. Kathryn Duncan

DVM, PhD, DACVM (Parasitology)
Sr. Professional Services Veterinarian,


Dr. Kathryn Duncan is a senior professional service veterinarian field specialist in parasitology for Merck Animal Health and an adjunct assistant professor in the Veterinary Pathobiology department at Oklahoma State University’s College of Veterinary Medicine.

She graduated from University of Tennessee’s College of Veterinary Medicine, completed a residency in veterinary parasitology through the National Center for Veterinary Parasitology, obtained a PhD in biomedical sciences at Oklahoma State University, and is a diplomate of the American College of Veterinary Microbiologists board-certified in parasitology.

Parasites are the most interesting ‘bugs’ out there! I can barely contain my excitement when I get to teach others the most efficient ways to protect our pets against these ubiquitous threats.

Dr. Duncan has been involved in a number of research projects and publications in companion animal parasitology, mainly focused on vector-borne diseases, ticks, and canine gastrointestinal parasites. She is a current member of various parasitology organizations such as American Heartworm Society and American Association of Veterinary Parasitologists.


  • Bachelor of Science, Animal Science, University of Tennessee
  • Doctor of Veterinary Medicine, University of Tennessee College of Veterinary Medicine
  • PhD in Biomedical Sciences, Oklahoma State University
  • DACVM, Board-certified in Parasitology

Areas of Interest

  • Clinical Parasitology
  • Diagnostics parasitology
  • Vector-borne diseases
  • Veterinary wellbeing


  • Duncan KT, Sundstrom KD, Hunt D, Lineberry MW, Grant A, Little SE. 2022. Survey on the presence of equine tick-borne rickettsial infections in southcentral United States. J Equine Vet Sci. 118, 104135.
  • Duncan KT, Elshahed MS, Sundstrom KD, Little SE, Youssef NH. 2022. Influence of tick sex and geographic region on the microbiome of Dermacentor variabilis collected from dogs and cats across the United States. Ticks Tick Borne Dis. 13, 102002.
  • Duncan KT, Grant A, Johnson B, Sundstrom KD, Saleh MN, Little SE. 2021. Identification of Rickettsia spp. and Babesia conradae in Dermacentor spp. collected from dogs and cats across the United States. Vector-Borne Zoo Dis. 21, 911–920.
  • Duncan KT, Saleh M, Sundstrom K, Little S. 2021. Dermacentor variabilis (Acari: Ixodidae) is the predominant Dermacentor spp. feeding on dogs and cats across the United States. J Med Entomol. 58, 1241–1247.
  • Duncan KT, Clow K, Sundstrom K, Saleh M, Reichard M, Little S. 2020. Recent reports of winter tick, Dermacentor albipictus, from dogs and cats in North America. Vet Parasit Reg Stud Reports. 22, 100490.
  • Duncan KT, Sundstrom KD, Saleh MN, Little SE. 2020. Haemaphysalis longicornis, the Asian longhorned tick, from a dog in Virginia, USA. Vet Parasit Reg Stud Reports. 20, 1–3.
  • Duncan KT, Koons N, Litherland M, Little S, Nagamori, Y. 2020. Prevalence of intestinal parasites in fecal samples and estimation of parasite contamination from dog parks in central Oklahoma. Vet Parasit Reg Stud Reports. 19, 1–5.