The clock is ticking down to Island’s tick season

Experts say now is the time to start building a strong defense against ticks and the myriad diseases they can carry.

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In the springtime, the nymphal deer tick can be as small as a poppy seed. — Photo by Jim Gathany, Wikimedia

Tick season on Martha’s Vineyard usually begins right around the time the Red Sox return to Fenway Park. This year, however, the diminutive disease carriers are already showing up, barely two weeks into spring training.

“They’re definitely active,” said Eddie Spindola, proprietor of Oh Deer, a company that applies organic repellents for insects and deer. “Usually we don’t start spraying until April, but they’re out earlier this year. We’ve been getting a lot of calls.”

Martha’s Vineyard is home to three varieties of ticks: the ubiquitous dog, or wood, tick; the deer tick; and the newly arrived Lone Star tick. Each is capable of transmitting a menu of diseases.

Dog ticks, which can transmit Rocky Mountain spotted fever and tularemia, are relatively large when compared with the blacklegged (deer) and Lone Star ticks. “Dog ticks are the main vector for tularemia,” Sam Telford, professor of infectious diseases at the Tufts University School of Veterinary Medicine and internationally known authority on ticks and tickborne diseases, told The Times. “The reason pneumonic tularemia is seen more on Martha’s Vineyard than in the Midwest, where there is more tularemia in general, is because the soil on Martha’s Vineyard is heavily salt-influenced, and the tularemia bacteria survive longer in that soil.”

In addition to Lyme disease, deer ticks also carry anaplasmosis, babesiosis, and ehrlichiosis.

Because of their small size, deer ticks in the nymphal stage are far more insidious. They can be as small as a pinhead, and the numbing analgesic in their saliva can make their tiny bite almost undetectable.

Mr. Telford said the deer tick nymphs should begin showing up next month. “Ticks are in the nymphal stage from April through the end of June,” he said. “They’re the ones we’re most concerned about.”

No deer tick nymphs have been reported yet. But the mites of spring are coming. Experts say there is still time for Islanders to take defensive measures that can significantly reduce the odds of contracting a tick-borne disease.

Prioritize pruning

“I’d say one of the biggest things people can do is to clean up leaf litter around the yard,” Dick Johnson, field biologist for the Martha’s Vineyard Boards of Health Tick Borne Disease Council (TBDC) told The Times. “Ticks love dark, moist places. Leaf litter is ideal for them.”

Mr. Johnson also recommends eliminating or pruning invasive plant species such as honeysuckle.

Other invasive species that ticks favor include bittersweet, autumn olive, and rhododendrons. “I’d advise people to trim their rhododendrons, as well as any bushes and shrubs that provide cover close to the ground,” he said. “I would also encourage people who have shaded yards to have their tree branches trimmed so their yard gets more sun.”

Controlling or eradicating invasive plant species is no easy task. Matt Pelikan, restoration biologist for the Nature Conservancy, wrote in an email to The Times, “Unfortunately, invasive plants are, almost by definition, difficult to get rid of, and eradicating them by cutting or digging often requires persistence over many years. As undesirable as the use of toxic chemicals is, careful and precise use of herbicide is sometimes the only feasible way to eliminate a population of an invasive plant, posing a difficult choice for a landowner.”

Matt Poole, Edgartown board of health agent and member of the TBDC, stressed that people need to take precautions before clearing brush or raking leaves.

“They should be wearing clothes treated with permethrin and shoes treated with DEET,” he said. “I spent about four hours clearing brush over the weekend, and I felt pretty confident that I’d taken proper precautions. If you really practice everything we recommend, you can substantially reduce the risk of infection from a tick bite.”

An added bonus of permethrin is that it doesn’t just repel ticks, it also kills them. Permethrin is the active ingredient in lice shampoos — it’s safe for children and for dogs, but not for cats.

Mr. Poole said homeowners can also deter ticks from entering their property with a two- to three-foot barrier of crushed stone or mulch around the perimeter of their yard.
“The lack of moisture in the gravel keeps them out,” he said. “Mulch works too, but you have to keep replacing it.”

“There’s a yard I check in Chilmark that has mulch around the perimeter and around shrubs, and I hardly ever find any ticks,” Mr. Johnson said. “Then I walk 20 feet to the neighbor’s yard, and there are plenty of deer ticks.”

There is one tick, however, a relative newcomer to the Island, that isn’t deterred by gravel or mulch — the Lone Star tick.

Lone Star rides into town

Mr. Telford has been doing field studies on the Vineyard since 1994. Prior to last summer, he said, he’d found the occasional Lone Star tick, but no concrete evidence that they had colonized here.

But last summer, that all changed. Mr. Johnson’s field studies confirmed that the Lone Star tick has indeed set up camp on Martha’s Vineyard. “They’re absolutely colonizing here,” he said. “The more I talked to people, the more I found them.”

Mr. Johnson said he found Lone Star ticks in all six Island towns, and that the hot spots were Chappy and Aquinnah.

Mr. Johnson said 30 to 60 percent of Lone Star ticks carry the Rickettsia amblyommii bacteria that causes spotted fever. A very small percentage of Lone Star ticks also carry ehrlichiosis, STARI (Southern tick-associated rash illness, which has symptoms similar to Lyme disease) and tularemia.

Unlike deer ticks and dog ticks, which passively wait for their blood meal to walk by, the Lone Star tick is an aggressive predator.

“It’s amazing how fast they can move,” Mr. Johnson said. 
“They’re nasty; they have eyes, unlike deer ticks which are blind,” Mr. Telford said. “They can see you and come after you.”

The female Lone Star tick is often distinguished by the white “star” on her back; however, not all Lone Star ticks have the white spot. “All of them, however, are round and brown,” Mr. Telford said. “And they all move fast.”

Lone Star ticks lay up to 6,000 eggs at a time. Their egg casings resemble a small bubble, usually attached to a leaf. “When I was in Aquinnah I was in the scrub for about 20 minutes, and when I came out I had about 500 tiny [Lone Star] ticks on each leg,” MR. Johnson said. “Luckily I had permethrin on my pants.”

Mr. Johnson said that, similar to the deer tick nymph, the Lone Star nymph can latch on and remain undetected because of its diminutive size and the numbing agent in its saliva. “You don’t know you’ve been bitten until it starts to itch,” he said.

Mr. Johnson stressed that daily tick checks are an important part of prevention. “If you’ve been outside, check yourself,” he said. “Make it part of your daily routine. Lots of times when you soap up in the shower you feel that little bump. That’s often the way I find them.”

A study done by the Vector-Borne Disease Research Laboratory in Maine concluded there is a definite link between invasive shrubs and the risk of exposure to tick-borne diseases. “First and foremost, honeysuckle alters the habitat use of white-tailed deer, which in turn alters the abundance of Lone Star ticks and human risk of exposure to the bacterial pathogens that they vector,” the report states.

A study done under the auspices of the National Academy of Sciences concluded that honeysuckle “increases human risk of exposure to ehrlichiosis, an emerging infectious disease caused by bacterial pathogens transmitted by the Lone Star tick.”

Tick so facto: deer = ticks = disease

Between 2010 and 2014, Chilmark was the Massachusetts town with the highest proportion of confirmed and probable cases of Lyme disease — 1,316 cases per 100,000 residents, according to data from the Massachusetts Department of Public Health.

According to a 2013 deer-density study done by Thomas Millette, director of the GeoProcessing Laboratory at Mount Holyoke College, Chilmark also had the highest deer density in the state, approximately 50 deer per square mile.

“It’s no coincidence that the concentration of Lyme [disease] is where you have deer habitat and human habitat, along with strict limitations to hunting,” Mr. Telford told The Times in an email. “This is the genesis of the rapid increase of Lyme disease in eastern Massachusetts. Except for cars, deer have no predators. I’ve found over 300 ticks on one deer. Multiply that by 2,000 ticks for every deer-fed female tick, and you get a sense of how crucial this is.”

“Culling the deer herd is a critical part of the equation,” Mr. Poole said. To better cull the deer population on the Island, the TBDC is currently in discussions with hunters, caretakers, and landowners to open up more area for hunting. “It’s kind of like a matchmaking service to pair up responsible hunters with landowners who might have historically not been open to hunting,” he said.

Mr. Poole said that hunters often say the state law that bans hunting on Sunday is a significant impediment, since most of them work during the week, effectively leaving them with one day a week to hunt.

But there is a bill on Beacon Hill that can change that. Mr. Poole said hunters and concerned citizens can take an active role in removing the Sunday ban by writing to State Senator Karen Spilka, chairman of the Ways and Means Committee, in support of bill S. 415, “An Act expanding the powers of the director of Fisheries and Wildlife.” S. 415 proposes to allow bow hunting on Sundays and legal holidays during the hunting season.

“Now is the time for people to write letters,” Mr. Poole said. “If we don’t take action and practice prevention, we’re resigning ourselves to a lot more people contracting tick-borne diseases.”

More information about ticks and prevention of tick-borne diseases can be found on the TBDC website mvboh.org and the website for the Centers for Disease Control, cdc.gov/ticks. To schedule a yard assessment, email Dick Johnson at rwilcoxjohnson@yahoo.com.