Key Points:
- A new ultra-sensitive DNA test was able to successfully detect Lyme disease in a sick horse, where other methods failed.
- The method hones in on the offending DNA, in this case Borrelia burgdorferi DNA.
- The test holds promise for adapting to other diseases and patients, including dogs and humans.
An 11-year-old Swedish Warmblood mare was sick, and the Cornell University School of Veterinary Medicine team couldn’t figure out why.
They suspected Lyme disease, but the PCR test did not detect the offending bacteria—Borrelia burgdorferi. That’s when Lyme expert Steven Schutzer, a professor of medicine at Rutgers New Jersey Medical School, stepped in.
Using a sample of the horse’s spinal fluid, Schutzer and his team employed their “genomic hybrid capture assay,” a highly sensitive test they developed. The test works by first selectively isolating DNA from the microorganism causing the disease.
“The method is like having a special, specific ‘fishhook’ that only grabs Borrelia DNA and not the DNA of other microbes, nor the DNA of the host (animal or human),” said Schutzer. “Detecting DNA of the disease is a direct test, meaning we know you have active disease if it’s circulating in the blood or spinal fluid.”
The ultra-sensitive DNA test positively identified the pathogen in the sample, allowing diagnosis and successful treatment of the horse.
Lyme disease in horses can cause long-term complications that include damage to the nervous system, joints, skin and even vision—similar to how the disease affects humans.
“The diagnosis of Lyme neuroborreliosis in horses is rarely confirmed antemortem and has frustrated veterinarians for years,” said Thomas Divers, co-chief of the Section of Large Animal Medicine at Cornell University’s College of Veterinary Medicine. “This is a very promising technique. Focused treatment against B. burgdorferi administered in this case resulted in the horse’s complete athletic recovery.”
While it’s still early, the ultra-sensitive DNA test developed by Schutzer’s lab could have applications for the detection of Lyme, as well as other difficult-to-detect illnesses, in dogs and humans in the future.
Information provided by Rutgers University.