Tick-Borne Diseases See Rise; Task Force Studies Prevention

By IAN FEIN
The Vineyard Gazette
Martha's Vineyard

To many Vineyard visitors, Memorial Day marks the beginning of summer.

But to an ever-increasing percentage of the Island population, it represents the start of the tick-borne disease season.

And early reports suggest that the Island may be in for an especially tick-ridden summer. Deer ticks thrive in damp environments, which the wet spring and winter weather has certainly provided.

"There are definitely truckloads of ticks out there right now," said Island biologist Luanne Johnson, who has been studying the Vineyard's skunk population. "When I was capturing skunks in mid-April they would have about zero to five ticks on their body. Starting in early May I was finding 20-plus ticks on each animal."

This is the time of year when hordes of young nymph deer ticks begin to show up in Island grasses. The nymphs - which can be smaller than a poppy seed and are much harder to detect - are responsible for more than 85 per cent of deer-transmitted diseases.

Vineyard deer ticks have been known to transmit debilitating bacterial diseases such as tularemia, babesiosis, ehrlichiosis and Lyme disease.

The Health Report of Martha's Vineyard, a comprehensive health study made public this winter, confirmed that Lyme disease has reached epidemic levels on the Island.

According to the report, more than 12 per cent of full-time residents and seven per cent of part-time residents said they have been diagnosed or treated for Lyme disease. One in five Vineyard residents said they have had some form of a documented tick-borne disease.

The problem is even more profound up-Island, where 37 per cent of Chilmark residents and 34 per cent of West Tisbury residents said they have had a documented tick-borne disease.

The increasing numbers led to the formation of a tick task force - an informal committee that is trying to find ways to stem the public health epidemic unfolding on the Vineyard. Most members of the group have either contracted a tick-borne disease or have a family member who has.

With tick season on their minds, eight task force members met at the Polly Hill Arboretum on Wednesday to discuss different initiatives to control the tick problems on the Island, as well as the political hurdles that stand in the way.

Probably the most effective means to lower the tick population on the Vineyard is to reduce the Island's deer herd. Adult female ticks feed on large animals like deer during the fall and winter. One deer can feed dozens of ticks, and each female tick can lay between 2000 and 3000 eggs.

MassWildlife estimates the Island has between 30 and 60 deer per square mile. The tick task force would like to see the number reduced to under 15.

The easiest way to decrease the deer herd is through increased hunting. But so far such initiatives have met with opposition.

Task force members on Wednesday decided to ask the Dukes County commission to invite MassWildlife to schedule a public hearing on the Vineyard this fall to consider changing the Island's deer hunting regulations.

Martha's Vineyard and parts of Cape Cod are currently the only areas in the commonwealth with one week of shotgun season. All other parts of the state - including Nantucket - have two.

"MassWildlife wants Martha's Vineyard to extend its season," said Sam Telford, a parasitologist from Tufts University who has been studying ticks on the Vineyard and Nantucket for the last decade. "The word from MassWildlife is - what the Vineyard asks for, it will get."

Mr. Telford told task force members about deer hunting initiatives on Nantucket that appear to have made a difference in the prevalence of tick-borne diseases. The second week of shotgun hunting instituted five years ago eliminates an additional 200 deer per year. According to state reports, Nantucket in 2003 saw a 37 per cent decrease in reported cases of Lyme disease while Dukes County saw a 55 per cent increase.

The difference was enough to put Dukes County ahead of Nantucket for the most per-capita cases in the commonwealth.

This winter, responding to a request from the Nantucket selectmen, MassWildlife tried a third week of shotgun hunting in February. The special one-week season attracted 600 hunters, many from other parts of the country, who killed about 250 deer on the island. MassWildlife was pleased with the results, but many Nantucket residents reacted strongly against it.

A petition with more than 1,000 signatures - many of them from Nantucket hunters - forced Nantucket selectmen to write a letter to MassWildlife rescinding their support for any future special seasons.

"I think it provides a useful lesson for us here," Mr. Telford said. "Avoid an extra shotgun season at all costs."

Mr. Telford said Vineyard hunters have told him they do not necessarily want additional shotgun time. They prefer archery season, which already lasts more than a month, he said.

But tick task force members noted that the one week of shotgun hunting on the Island last fall resulted in almost four times as many kills as the five-plus weeks of archery.

Task force members also discussed ways to create incentives for increased hunting during the existing seasons - possibly through a deer-hunting derby with prizes, a cold storage facility for meat, or by opening access to previously restricted properties. Task force members sent letters to Island conservation organizations and all up-Island property owners of five acres or more asking them to allow hunters on their land during the winter.

One way to control the tick population without killing deer is through a four-poster system, about 20 of which are spread around the Island. Deer feed on corn in troughs that are flanked by permethrin-coated rollers, which kills ticks on their heads, necks and shoulders.

But task force members believe hunting is a better option because the four-poster system requires ongoing funding for maintenance, corn and chemicals, and it goes against MassWildlife's policy prohibiting the feeding of deer.

Task force members this week also expressed frustration at the lack of communication among Island health care organizations about tick-borne disease prevention and treatment. They said they had not been informed of an upcoming tick-related community health forum hosted by the Martha's Vineyard Hospital.

An educator from the Massachusetts Department of Health will speak about staying safe during tick season at the hospital on June 15 at 7 p.m., and will conduct the same program with a Portuguese translator at 8:30 p.m.

Tick prevention techniques to keep in mind this summer include: Limit your time in grassy or wooded areas; if you go walking, wear long, light-colored clothing; check yourself and pets for ticks or tick bites once a day, feeling for new bumps and looking for rashes; and if you have an unexplained fever or flu-like symptoms, go see a physician.