Tick...Tick...Tick

“I was never very fond of bugs as a child,” quipped Thomas N. Mather, Ph.D., arguably Rhode Island’s best known entomologist. For nearly two decades, Mather and his researchers at the University of Rhode Island's Center for Vector-Borne Disease have worked tirelessly to understand ticks and the diseases they transmit to people and pets. But we’re not talking about those icky, bloated dog ticks that were quickly flushed down the toilet during the Ozzie-and-Harriet '50s.

“These ticks are different,” Mather emphasized this week during a presentation about black-legged ticks (Ixodes scapularis), commonly known as deer ticks.

Rhode Island At Risk

More than 50 URI Master Gardeners, from metropolitan and rural communities alike, gathered in Kingston at Weaver Auditorium in the University’s Coastal Institute on Tuesday evening for Mather's "Tick Talk." The group watched Hidden in the the Leaves, a sobering documentary film produced in Rhode Island by URI’s TickEncounter Resource Center .  

TERC is the go-to Website for all things tick. Click here to access links for viewing the documentary online on TERC or on YouTube.

“If anyone’s going to be exposed (to ticks and the diseases they transmit), it’s going to be a group of Master Gardeners,” Mather cautioned during his post-film presentation.

In fact, everyone in Rhode Island is at risk, he said, adding, “While the summer of 2010 was one of the lowest on record for nymphal stage deer ticks, this past fall the adult stage ticks were super-abundant.” With the heavy snow cover we experienced this winter, many more adult ticks are expected to emerge from their safe-haven leaf litter in the days ahead.

What's Old Is New Again

The first publicized cases of what we now recognize as Lyme Disease in the United States occurred in the mid-1970s in the Connecticut River Valley. But is Lyme Disease really new?

Not according to a Brown University Timeline of Important Events in the History of Lyme Disease. URI's Mather explained that mouse skin tissue samples from the 1800s at the Harvard Museum tested positive for the organism that would be identified a century later as Borrelia burgdorferi, the Lyme Disease-causing spirochete carried in the saliva of infected deer ticks. (Mather came to URI in 1992 from the Harvard School of Public Health.)

The white-footed mouse is the main rodent reservoir for these disease organisms. Ixodes ticks suck in the Lyme Disease bacteria as part of their mouse-blood cocktail.The infected ticks then inject the bacteria via their saliva into mammals such as deer and people. Like biological co-conspirators, the bacteria do not sicken their preferred hosts - the mice and deer. But they sure do sicken people!

This Google timeline search on “Ixodes tick history” shows references to the Ixodes genus of tick going back to the mid-1700s. Some of those early references are speculative at best. But they underscore the seeming ebb and flow that characterizes the history of tick diseases in the Northeast. URI’s Mather cited, for example, two old afflictions: Montauk knee, now known to have been Lyme Disease, and Nantucket fever, recognized today as babesiosis, another tick-borne illness.

Unlike Lyme Disease and human anaplasmosis, which is a second bacterial disease transmitted by infected deer ticks, babesiosis is caused by a malaria-like protozoan (Babesia microti) that embarks on a seek-and-destroy mission against red blood cells.

“Not a year goes by that we don’t have a death from babesiosis (in Rhode Island)," Mather said.

Shifting Populations

“In the 1700s,” explained Mather, Rhode Island was “mostly forest.” Settlers cleared the land for farming, building stone walls from the rocks they hauled out of the fields. Agricultural activity pushed wildlife including deer deeper into the forest.

As the industrial age supplanted agriculture, farms were abandoned and forests reclaimed the land. Even today you find stone walls in the middle of the woods. "Stone walls are like rodent condominiums," Mather said.

The post World War II period brought prosperity, cheap gasoline and suburban sprawl. People began clearing the second growth forests to build homes in rural areas like South Kingstown.

If you check the 2010 Census figures for Rhode Island that were released just this week, you will see that during the past 10 years there has been a continued exodus of people from cities to outlying towns.

Although some of us complain about deer invading our yards, is it more accurate to say we invaded theirs?

What Makes Ticks Tick?

Quite naturally, a deer tick’s raison-d’etre is to reproduce. To do that, ticks need to eat. “If they don’t suck blood, they don’t survive,” said Mather.

During its life cycle, which takes two years, the tick hatches from an egg as a larva, then develops into a nymph, and finally matures into an adult tick. According to Mather, about 25% of nymphs and 50% of adult ticks are infected with Lyme Disease.

While larvae and nymphs prefer to feed on the blood of small rodents such as the white-footed mouse, deer tick adults prefer to feed on the blood of larger mammals such as deer. However, ticks are among nature’s most enterprising opportunists. If you or your children venture into tick territory, those little draculas happily climb up, latch onto, and saw into your flesh. Ditto for pet dogs that romp beside us.

P for Prevention

Although a tick can bite you any time of year, most diagnosed cases of tick disease occur during the summer months. Warm weather brings people outdoors in closer proximity to nature. We sometimes forget that nature can be bloodthirsty.

Fortunately, you can prevent tick diseases by what we think of as The Three Ps. The points below incorporate Mather’s advice from Hidden in the Leaves and TERC:

• PEEPERS - Look around. Observe your environment and eliminate, whenever possible, habitats that potentially attract ticks, mice, and deer. These include bird feeders, rock walls and wood piles. Reduce humid areas favored by ticks by raking leaves and pruning shrubs and trees to allow more sunshine into your yard. Ticks don’t survive well in dry areas. After working or playing in your yard, look closely at all parts of your body or, more realistically, ask someone else to examine your backside. Those of us who are of a certain age will want to wear our 'cheaters' (reading glasses) because nymphal ticks are the size of poppy seeds. The TERC Website’s tick identification chart can help you learn what to look for. You’ll also learn how to remove ticks safely.

• PERMETHRIN - You can prevent tick diseases by killing ticks with products containing permethrin. Damminix Tick Tubes® are cardboard tubes containing permethrin-treated cotton balls; mice use the cotton to build nests and, in so doing, kill any disease-carrying ticks there. You can also hire local companies to spray your yard’s perimeter with permethrin. Permethrin-treated shoes and clothing are perhaps the most effective way to prevent tick bites. If you do nothing else in terms of your clothing, at least spray your shoes and socks with permethrin, available locally at on Main Street, Wakefield. You can likewise purchase do-it-yourself permethrin kits to treat pants, shirts, and other clothing items. You can also buy pre-treated clothing that provides protection against ticks for 70 washings.

• PATCH - Mather’s team is developing, along with two Providence biotech companies (EpiVax and Isis Biopolymer), a small bandage-size, transdermal Tick Bite Patch™ which immunizes the wearer against tick saliva. Research shows that people bitten by ticks tend to develop Acquired Tick Resistance (ATR), an immune response to tick bites. Before the tick can inject disease-causing organisms into the blood stream of these immune individuals, proteins in the tick’s saliva set off a mild sensitivity reaction - itching - which alerts them to the presence of the tick. The Tick Bite Patch™ would safely confer this type of immunity on all of us. Visit the TickEncounter Resource Center for details.

“Tick-borne diseases are completely preventable,” Mather assured the Master Gardeners this week.

Ask anyone who has suffered from Lyme Disease, human anaplasmosis, or babesiosis -  or all three simultaneously, like Harvey C. Perry II - and you realize that investing a small amount of time and money on prevention pays big dividends. In fact, your life could depend on it.

Click on the "View Gallery" link in the image at the top of this article to enjoy our photo gallery and to watch a video snippet of  Mather explaining how the Tick Bite Patch™ works.

To learn more about Mather’s work, visit the TickEncounter Resource Center web site or the TERC Facebook page.

Download the movie