A blacklegged tick, just the size of a poppy seed, perches on the tip of a leaf. It stands poised with its limbs outstretched, ready to latch onto its next prey.
It’s barely noticeable, but looks essentially harmless; just another tiny bug that will leave itchy red bumps up and down your legs. But that bite carries a greater threat: Lyme disease.
Lyme disease is the most common tick-borne illness, and generally causes a circular rash, joint pain and flu-like symptoms. The Centers for Disease Control and Prevention (CDC) estimates that it affects about 300,000 people in the U.S. each year. There were more than 1,400 confirmed cases of Lyme disease in Minnesota in 2013, and it has been found in four times as many counties in 2013 compared to 1993 nationwide. It’s most commonly diagnosed in the Northeast and upper Midwest.
It’s spreading, but there’s still a lot scientists and physicians don’t know about Lyme disease. Health Talk spoke with faculty at the University of Minnesota Medical School Duluth to learn more.
On the bacteria that causes Lyme disease…
We contract Lyme disease through Ixodes scapularis, commonly known as the deer tick or blacklegged tick. When they bite, they spit saliva into the body, which transfers Borrelia burgdoferi (Borrelia), the bacteria that causes Lyme disease. The saliva also protects Borrelia from macrophages that eat up viruses and bacteria. Borrelia just slide off and infect the body. Macrophages normally stimulate an immune response, but they can’t find the bacteria. As they multiply, the coating disappears, but at that point it has spread throughout the body.
On Lyme disease diagnosis…
It can be hard for physicians to detect Lyme disease because Borrelia elude an immune response. In other words, they hide.
“Early on, a test could be normal even if you have Lyme disease,” said Jacob Prunuske, M.D., associate professor of family medicine and community health at the University of Minnesota Medical School Duluth.
The test looks for Borrelia antibodies, which develop when the immune system kicks into gear. Most patients develop antibodies within a month of infection, but for about 20 percent of patients, they can take much longer to show up. While symptoms may be present, the test can be negative. And the rash, the telltale sign of Lyme disease, doesn’t develop in about 20-30 percent of patients.
“Aside from the rash, the main symptoms are fever, fatigue, joint pain and muscle aches. That could really be any type of virus,” Prunuske said. “It can be easy to miss Lyme disease in that context.”
On Lyme disease prevention…
The only foolproof way to prevent Lyme disease is to stay inside, but avoiding the outdoors is unrealistic.
“Check yourself for ticks,” Prunuske said. “Wear long pants and shirts to minimize exposed skin for ticks to bite.”
Ticks generally need to be latched to the body for at least 24 hours to pass on Borrelia. Even so, it’s important to regularly check for ticks and remove them quickly.
Our experts gave these CDC-recommended tick tips to keep in mind:
1. DO use a tweezers. Grasp as close to the skin as possible.
2. DON’T twist, jerk or shake in the process, or parts of the tick’s mouth (and the bacteria) could remain lodged in the skin. Do not burn them off and don’t try to crush the tick with your hands or feet.
3. DO clean the site of the bite with rubbing alcohol or soap and water.
4. DON’T wait to tell your doctor.
5. DO save the tick and send in for testing. This can help researchers, and could help your doctor identify Lyme disease sooner.
Lynne Bemis, Ph.D., Benjamin Clarke, Ph.D., Amy Prunuske, Ph.D., with the department of biomedical sciences are all researching Borellia, exploring how the bacteria move through the body and interact with antibiotics. They also hope to develop a more accurate test for diagnosing Lyme disease. Read more about their research and other UMN projects examining tick and vector-borne diseases.
The post From tick to sick: the search for a Lyme disease diagnosis appeared first on Health Talk.