For decades veterinarians have had an arsenal of safe and effective drugs for which to rely upon to manage common parasites in pets and agricultural animals.
But over the years, many parasitic species have developed varying levels of resistance to many of those drugs, creating challenges for veterinarians, including those like Dr. Laura Williams who has dedicated her career to the field of parasitology.
Williams, a licensed veterinarian at the Washington Animal Disease Diagnostic Laboratory at Washington State University, is one of fewer than 50 veterinarians in the United States board certified in parasitology by the American College of Veterinary Microbiologists (ACVM) and the only one in Washington. At WADDL, she serves as section head of the parasitology laboratory, a full-service diagnostic laboratory offering testing for the detection of parasitic infections in domestic and wild animals. Williams consults with the public, producers, and veterinarians in the identification, treatment, and control of parasites.
“The concern in parasitology is the resistance to medications – there are only a limited number of antiparasitics that we have available on the market,” Williams said. “I can’t speak about what is going to be available in the future, but it has been about 30 years since big classes have been released into the market, so there’s a lot of concern about once resistance develops in parasites like hookworms in dogs and cats or strongyles in horses and cattle, what do we do then? That’s why we have to figure it out before we get there.”
With resistance a growing concern, Williams is encouraging more sustainable solutions to parasite control and management, which means moving away from drugs as the sole management strategy. For large animal producers, many of these methods revolve around stocking density and maintaining a clean environment for livestock.
“Stocking density is by far the biggest contributor to too many parasites in animals,” she said. “Having too many animals in the same pasture just perpetuates the lifecycles of these parasites, and the animals can get overrun pretty easily. If you can spread out animals more and you can clean up poop from the pasture, that is probably going to make the biggest difference in controlling parasites.”
In addition to assisting with management practices and parasite control, Williams is also an expert at identifying parasites.
“As a pathologist and diagnostician, my job is to diagnose disease in animals. That interest extends to the identification of parasites too, whether they are sent to us from a live animal or we find them on a post-mortem exam,” Williams said. “It is nice that WADDL has the tools I need to be able to do that identification and ultimately help people control these issues in their animals.”
Williams earned a Doctor of Veterinary Medicine from WSU in 2013 and stayed at the university for a combined pathology residency and doctoral program, which she completed in 2018. She became board certified in pathology in 2019.
After earning her doctorate, she remained at WSU as clinical instructor, teaching a parasitology course to veterinary students. The course fueled her interest in the field and she took a more active role in the parasitology section at WADDL. In September of 2021, she became ACVM board certified in parasitology.