Using genetic testing to fight tick-borne disease
Tiny and often overlooked deer ticks are on the rise throughout Wisconsin and Minnesota. To better identify the diseases these under-sized critters can carry, Marshfield Clinic researchers have turned to molecular, or DNA-based, testing.
Tom Fritsche, M.D., Ph.D., (left) and Timothy Uphoff, Ph.D.
"Traditionally, we've had two primary ways to identify an infection," said Timothy Uphoff, Ph.D., section head of Molecular Pathology. "We could look at a blood smear through a microscope or use a blood sample for testing to see if antibodies from the disease are present."
These approaches are not always useful, however. It can take four to six weeks to finally get a diagnosis, and antibody tests don't always accurately differentiate new infections from past exposure. Disease symptoms can also vary widely, so even if a person knew of a tick bite, symptoms might not show up right away for Lyme disease or one of the other common tick-borne diseases, anaplasmosis and babesiosis.
A collaborative research effort between Marshfield Labs, in partnership with Marshfield Clinic Research Institute (MCRI), helped develop new testing methods that are far superior. Like other recent developments in medicine, these molecular tests focus on DNA, the genetic code found in all living things. But in this case, it's not human DNA but rather the DNA of the bacteria or parasite responsible for infection after a bite from an infected tick.
"Our new DNA-based testing methods are far more accurate and faster," said Tom Fritsche, M.D., Ph.D., a Marshfield Clinic pathologist and head of the Clinical Microbiology Section. "Patients can get the appropriate treatment sooner and get well faster."
Dr. Fritsche praised the work of Core Lab Researcher Anna Schotthoefer, Ph.D., and colleagues at MCRI.
"They've done nice work at the basic science level, providing vital information about each of the tick-borne diseases in our region and how they can be detected," he said. "We, on the clinical side, couldn't have developed our diagnostic tests for patient use without them." Dr. Fritsche noted there is considerable interest in these diseases in Europe, where Clinic researchers recently presented a paper on their experiences.
Although the new DNA tests allow for faster and more accurate results, Dr. Uphoff advises that the usual precautions still apply. When in the woods, keep your skin covered with long pants and shirt sleeves and tuck your pant-cuffs into your socks. Use a repellent, preferably containing DEET.
Anyone interested in supporting tick-borne disease research efforts at Marshfield Clinic should contact the Development Department at 715-387-9249.