This article was written by Meredith King and originally published on the UVM Brainwaves Blog, published by University of Vermont Continuing and Distance Education. See more at: http://learn.uvm.edu/health-blog/lyme-disease-on-the-rise-in-vermont
Ten or 20 years ago, most Vermonters never gave Lyme disease a second thought. It was a distant threat, something that people in, say, Connecticut, New York, New Jersey or Massachusetts worried about.
Now you don’t even have to leave the Green Mountain state to hear about someone’s experience with Lyme disease.
That’s because Lyme has spread at an incredible rate over the past decade in Vermont, from 60 cases in 2003 to 890 cases – 671 confirmed and 219 probable – in 2013, according to state epidemiologist Erica Berl, D.V.M., M.P.H.
Yet Berl and other scientists don’t know why Lyme now has a stronghold here.
“It’s multifactorial. Clearly, Lyme disease has been spreading out in all directions across the United States – north, south, east and west – over the last several decades,” Berl says. “It was inevitable that it would come up here.”
What is Lyme Disease?
Lyme disease is caused by infection with the Borrelia burgdorferi bacteria. The infection is transmitted by the bite of the deer, or black-legged, tick. The disease got its name from Lyme, Conn., where a cluster of children and adults came down with arthritic conditions in 1975 that later were linked to the ticks and, in 1982, to Borrelia.
Over the past decade, Connecticut often ranked as one of the top three states for incidence of Lyme disease. However, in the latest two years of rankings by the U.S. Centers for Disease Control – 2011 and 2012 – Connecticut slipped out of the top three.
And which state moved into the top three during the same time period, helping bump out Connecticut? Vermont.
Lyme Disease Makes its Way North
In 2012, Vermont had the third highest incidence of Lyme disease in the nation, behind No. 1 New Hampshire and No. 2 Maine; in 2011, Vermont was ranked No. 2. About 75 percent of Vermont’s Lyme cases originate in the state, according to Berl.
Many scientists trace the spread of Lyme disease northward to the movement of white-tailed deer, Berl explains. Deer carry the ticks but do not become infected with Borrelia.
“The white-footed mouse is the natural reservoir for Borrelia, so where you have the mice and the deer, the Borrelia becomes established,” she says.
Others have posited that global warming may play a role in the spread of Lyme disease. Yet another theory is the suburbanization of forestland.
In Vermont, the age groups most affected by Lyme disease include children and teens ages 5 to 18 and adults ages 45 to 65, she says.“That theory says that we divide up the land into small plots, and that favors small rodents, which are the best reservoirs for the Borrelia,” Berl says. “In Vermont, we’re not developed like suburban areas, but we have lots of good habitat for deer and mice.”
“The assumption for kids is exposure – they are outside a lot running around – and they’re not good at doing tick checks,” she says. “For the middle-aged adults, we don’t know why” they are more susceptible.
Preventing Lyme Disease
Christopher Grace, M.D., an infectious disease specialist at the University of Vermont Medical Center and professor at the Larner College of Medicine at UVM, says prevention is key to fighting Lyme disease.
“First, try to avoid getting the tick on you. Second, if it’s on you, get it off,” Grace says.
Grace offers these preventative steps:
- If you’re headed into grassy or wooded areas where ticks like to hang out, then wear long pants, tucked into your socks, and long-sleeved shirts. If it’s hot and you’re wearing shorts, then be extra diligent with tick checks.
- Spray Permethrin onto your clothes and shoes to repel ticks. You also can buy Permethrin-impregnated clothes.
- Use a 30 to 50 percent DEET-based product on your skin; it has been found to be safe for you and your kids, Grace says. “DEET on has been on the market for 30 years. It’s the only thing that has been shown to have efficacy in keeping ticks from attaching,” he explains. “Just make sure you wash it off at the end of the day.”
- Check for ticks after you’ve been outside. They can crawl all over your body, he says, and “you need to look in all the nooks and crannies.” Although adult ticks are easy to find, nymphs are not; they can be as small as a pin prick. Pay special attention at key times for the nymph phase of ticks: spring and early summer.
- If you find a tick, use tweezers or a special tick remover to get right at the edge of your skin and pull off the tick. If the pincers are left behind, that’s OK; they don’t contain Borrelia. And don’t go digging around to remove any remaining pieces. You don’t want a secondary Staph infection. Wash the area with soap and water.
- If you do remove a tick, watch for signs of rash, but don’t assume that the lack of a rash means you won’t get Lyme disease. “About 80 percent of people will develop these classic rashes, but the vast majority of rashes are not target lesions – the big bull’s eye. Instead, they are big, red, oval rashes,” Grace explains. “Also, where the tick bites you, you may get a localized irritation. It may get red, and it may get itchy.”
- The early acute stage – where you may or may not see a rash, and you may feel achy and tired, like you have the flu – is the best time to ward off Lyme disease with treatment with a dose of antibiotics, Grace says. This stage occurs three to seven days after a tick bite.
- And finally: “Not every tick has Lyme in it, and not every tick transmits it. The fact that you have a tick on you doesn’t mean you’ll get Lyme disease,” he says. “Also, the general rule of thumb is: If a tick has been on you for less than 48 hours, you are probably not going to get infected with Lyme disease.” That’s because the process in which the tick sucks your blood into its stomach and then re-injects this mixture back into you takes 36 to 48 hours. “So if a tick is not engorged, it hasn’t transmitted Lyme yet.”