Part Five: Tick Control
By Sean Corcoran
August 17, 2012
Walk into Eastern Mountain Sports in Hyannis, and the anti-tick clothing is straight ahead towards the back.
Eric Johnson is the store manager. He points to a rack of egg-white shirts and light, khaki-colored pants.
"You notice these garments are long sleeve and long pants," Johnson said, "because if you're not covering these parts of you body, it can't do its job."
Impregnated in the fabric of these clothes is an insecticide and repellant called "permethrin." It's the most commonly-used chemical weapon in the war against ticks. In a way, permethrin comes from flowers. But it's man-made, a synthetic version of a naturally-occurring extract from the chrysanthemum flower. It's in lots of insecticide products -- from lice shampoos to bug bombs and mosquito sprays.
"In our footwear department, we have something called gators," Johnson said. "And no, it's not an animal that swims through the water in Florida."
Gators are pieces of fabric that prevent rocks and twigs from getting into the top of your shoe or boot. These have been treated with permethrin to keep the ticks out too. Over in the hat department is a head bandana that's been treated with permethrin. Johnson says lots of customers are looking for anti-tick stuff.
"It's growing immensely," he said. "Not only through the clothing market, but also some of the applications you can put on your on clothes. But also on your skin, on your body. Let me show you those…"
Permetherin is highly toxic to honeybees, fish and cats. It's also not for use directly on human skin. For the skin, the well-known mosquito repellant DEET is what's often recommended.
But what if we forget it at home, or don't want to use it? Maybe we neglect to wear the long pants or to respray the hiking boots before hitting the trail? One edge we have is that ticks need to drink blood for a good 24-hours before they can pass along Lyme and other diseases. So there's some time to take action.
"After all," Johnson said, "either prevention in the first place, or diligence in removing or finding ticks off your body is the next step. In fact we have one product called the 'tick key,' which is specifically designed to pull ticks off your body if indeed they get in there."
Permethrin is a key chemical when it comes to preventing ticks from getting on us, and researchers and private companies also are developing innovative ways to get permethrin onto the animals ticks feed upon.
Richard Ostefeld is a leading tick researcher and a senior scientists at the Cary Institute of Ecosystem Studies in Millbrook, New York.
Ostfeld says American scientists are looking at different fungi that might be used against ticks. They're exploring vaccines that would have the body attack the actual tick as soon as it latches onto us. And there's been work with natural tick enemies, such as parasitic wasps that reproduce right inside the tick.
Right now, one of the most promising methods to cut down on tick numbers is something called a 4-post deer feeding station: Attract deer with corn, then give em a good dose of permethrin while they're eating.
"You can kill about 70 percent of the ticks if you run these things year after year," Ostfeld said. "You can't stop because the ticks bounce right back. But if you have the deer stations deployed permanently then you can put a big dent in the tick population."
These feeding stations are refrigerator-sized, plastic boxes baited with a few hundred pounds of corn and armed with 4, 9-inch paint rollers. The rollers are treated with permethrin, and to eat, an animal must brush against them. The permethrin kills any adult ticks on the deer before they can lay eggs. And one of the reasons Ostfeld and others are optimistic that the stations could make a difference is because they don't just treat deer but also other large mammals that are involved in the lifecycle of the tick.
"It's true that this 4-poster deer feeding station is targeted at one host, i.e. the white tail deer," he said. "But it turns out that when you put a huge bin of corn out in the woods, you attract almost every mammal and a lot of birds out there in the wood. So even though the device is geared toward one species, there's excellent evidence these 4 posters attract raccoons, skunks, opossums, coyotes, turkeys, crows… you name it."
The stations are labor-intensive to operate. There's also concerns about leaving large quantities of insecticides in the woods where children could get at them. There are several of these feeding stations on the Cape and Islands, part of a research project that began about five yeas ago thanks to Barnstable County's former entomologist, David Simser. His successor, Larry Dapsis, says the program is on hold as the EPA reviews data from past few years.
"We don't have a conclusion at this point in time," he said. "So we've got work to do before we kind of say is this ready for prime time or not?"
Dapsis says the feeding stations counter the argument some people make that the solution to fighting ticks is killing deer -- one of the primary hosts for adult-stage ticks.
"We've taken Bambi and turned Bambi into Rambo. A tick killing machine that works 24/7 on our behalf," he said. "So as long as the deer are upright and walking around in the woods picking up ticks, this is effectively killing them."
Researchers know that younger ticks often find their way onto smaller animals such as mice, chipmunks and shrews. So, a private company is expected to return-to-market a device called a 'bait box', a small plastic box with food bait that can attract smaller animals and treat them with insecticide.
Ostfeld says it's possible that tick-heavy regions could benefit from combining bait boxes with the 4-poster stations.
"The more of these device you have out," he said, "the higher the percentage of the rodent population you are going to be treated. Again, you have to have it out at least at the right time of year every year."
At Nickerson State Park in Brewster, it's July and the nymph-stage ticks are out looking for blood meals. Dapsis, the county entomologist, waves a piece of white cloth in the brush next to a walking path and shows it to the Duffy family from New Jersey.
"This is a deer tick," he said. "A nymph-stage deer tick."
On the flag of cloth is a shockingly small tick, barely the size of a poppy seed. Real tiny. And it was in the leaves and grasses where the sandal-footed family was walking.
"A black speck," said one child.
"Boy, those are really tiny," said his mom. "We'll have to double-check when we get back to the campsite."
"The kind of the message here overall," Dapsis said, "is that tick bites and tick borne diseases is 100 percent preventable. You have to really think about it, though, like hand to hand combat. And every battle you have with a tick you want to win. So that's why, take the upper hand. Things like repellants, repellant clothing. Tick checks. Tumble dry your clothes. You do all those things, you should not have an incident with a disease."
Political discussions about Lyme Disease have been ongoing since the 80s. But with more people becoming infected, and with other tick-borne diseases on the rise, some lawmakers are paying attention. A Beacon Hill commission is working on a set of recommendations for better treatment and awareness of tick diseases, as well as suggestions for controlling tick populations. One discussion underway is combining existing mosquito-control efforts with a tick-spraying program. Officials aren't sure yet if that's even feasible. But they are certain that more people need to know just what they're up against in the fight to remain tick -- and disease-- free.