Vineyard Epidemic: Lyme Disease on the Rise: Health Experts Track Cases
Martha's Vineyard Gazette - Edgartown,MA,USA
By BRIEN HEFLER
The Martha's Vineyard Hospital reports a large increase in Lyme disease cases this summer - over double the number seen last year - fueling concerns about what many public health experts say is now an epidemic of the disease carried by tiny deer ticks.
Donna Enos, infections control nurse at the hospital, said case reports submitted by emergency room and primary care physicians show a sharp increase in Lyme disease over last year's numbers, with 40 cases in June, 110 in July and 105 in August. Mrs. Enos predicts September will show an increase as well due to warm weather.
"September is looking very high too; let's not forget the temperature out there, it's like August all over," she said.
The numbers reflect diagnosis by hospital doctors. Final confirmation will come through the Massachusetts Department of Public Health (DPH), a process that takes several months.
Surrounded by a sheaf of case reports for the summer, Mrs. Enos spoke from her office this week about the incidence of tick-borne illness on the Island.
"This year is significantly greater than years past on what I'm reporting right now, but the final word will come from the DPH," she said.
Each case of Lyme disease diagnosed in the hospital is documented using a reporting form from the state DPH. Mrs. Enos said the process is lengthy and final numbers will not be available until winter. Every case submitted by the hospital must meet a strict set of criteria to qualify as a confirmed Lyme disease case. Some Lyme disease cases seen on the Island may not be reported, including cases involving visitors who contract the disease and return to their home state for treatment.
In short, the actual number of cases may be higher than reported.
Dr. Frederic Cantor, a public health veterinarian for the DPH, agreed the numbers may not reflect the complete number of Lyme disease cases seen on the Island, but he said guidelines are necessary when comparing the number to state and national totals.
"For our statistical, yearly evaluation, we need to make sure we're talking about the same thing year to year," Dr. Cantor said, "There may be some cases that we cannot capture that are clearly [Lyme disease] but without the recording and information they get put into different categories."
While the final tally is not yet available, Dr. Cantor agrees that there has been an increase in Lyme disease cases this year, along with other tick borne illnesses. Already, the DPH has confirmed eight cases of tularemia on the Island this year and is investigating four more. While rare in other parts of the nation, tularemia seems to flourish on the Island, with 37 confirmed cases seen since 2000.
The Health Report of Martha's Vineyard, a comprehensive study of health issues in the adult population on the Island done in 2002 and 2003, found epidemic levels of Lyme disease. A draft final report completed late last year found one in five full-time residents reported having a tick borne illness, and 12 per cent reported having had Lyme disease. Seven per cent of part-time residents also reported having either been diagnosed or treated for Lyme disease.
The rate of Lyme disease was even higher for up-Island residents.
Dr. Cantor and Mrs. Enos both said the increased numbers this year can at least partly be attributed to better reporting by Island doctors.
Mrs. Enos said emergency room doctors at the Island hospital have quickly become experts at recognizing Lyme disease and other tick borne illnesses.
"I don't think [the increase] is because there are more ticks, but more awareness," Mrs. Enos said.
But Dr. Cantor and Mrs. Enos also believe weather is a factor. Mrs. Enos said a wet winter coupled with a warm, dry summer means more people venturing into areas where they are exposed to ticks, including woodlands and beaches.
Dr. Cantor agreed.
"I think it's a combination of things. It's not just the increased vigilance at the hospital because we've had that since 2000," he said, adding: "I think the weather again is warmer and lasting longer, so there are going to be more exposures. We see that for a lot of diseases, like rabies - if it's something that's weather dependent it means people either have to go out there and be exposed or that the bugs aren't there."
Dr. Bela Matyas, medical director of epidemiological studies for the DPH, said the large deer population on the Island give deer ticks an ideal breeding ground. Deer ticks, which carry Lyme disease, use large mammals such as deer to lay eggs.
"You have the perfect ecology for [Lyme disease] and animals that are important in the cycle that transmit it - the only natural predators on the Island [for deer] are automobiles and there are no other predators that keep the process in check," he said.
Dr. Matyas said studies have shown that reducing a deer population has a direct correlation on the number of deer ticks. One female deer tick can lay between 2,000 and 3,000 eggs and one animal can support dozens of ticks. A task force formed earlier this spring began to examine the question of reducing the deer population, including extending the hunting shotgun season from one week to two weeks. The Island is the only region in the commonwealth with a one-week shotgun season.
Five years ago Nantucket added a third week to shotgun season for deer, and lowered the deer population by an additional 200. But the additional hunting saw vocal opposition from some residents, and Nantucket selectman have since opted to return to a two-week season.
Health experts say prevention is still the best cure. Mrs. Enos recommends people take all necessary precautions to prevent tick bites, such as tucking pants into socks, wearing light colored clothing so ticks are easier to spot and applying tick repellents with a concentration of DEET no greater than 30 per cent. If a tick is found, Mrs. Enos advises slow and careful removal, using tweezers or special removal tools like the Pro Tick Remedy - small, precession tweezers designed for tick removal and available at the hospital. She also reminded people to thoroughly wash the area where the tick was found, as well as the hands after removal. Avoid crushing ticks with bare hands or touching the face or mouth before washing hands, Mrs. Enos said.
Fast action is also important when symptoms appear. Mrs. Enos said anyone who experiences symptoms associated with Lyme disease such as headache, joint pain, fever or facial paralysis, should seek immediate medical attention.
