MASSACHUSETTS NEWS: Lyme Disease Cases Tick Upwards

Lyme disease, the tick-borne ailment once primarily a scourge of the Cape and Islands, is now rampant in swaths of Massachusetts where locally acquired cases were rare a decade ago.

In Middlesex, Norfolk, and Worcester counties, the number of patients diagnosed with the bacterial disease surged more than fourfold between 2000 and 2009, according to figures the state Department of Public Health provided to the Globe.

The increase, which is fueling a statewide increase in reports of symptoms, is evident in the offices of infectious disease specialists and primary care doctors in places like Framingham and Natick, where Lyme disease diagnoses 10 or 15 years ago were largely restricted to people who had visited Cape Cod.

“Now,’’ said Dr. Richard Ellison, hospital epidemiologist at UMass Memorial Medical Center in Worcester, “they’re living in Charlton, they’re living in Northborough, they’re living in Westborough. And they’re not traveling to the Cape.’’

The disease is on the move, special ists said, because the deer population is expanding and human developments are encroaching on natural habitats. Hundreds of ticks can hitch a ride on a single deer. And a lone female tick can lay 2,000 — or more — eggs.

The result: Human and tick have increasing opportunity to come into contact, spreading an illness that often manifests with flulike symptoms but in some cases causes serious cardiac and neurologic complications.

It is an illustration, too, of the difficulty containing infectious diseases, especially those carried by tiny insects. The young ticks that tend to attach themselves to humans are roughly the size of a poppy seed and hard to detect. Their favorite hiding spots are behind knees, in armpits, and in the groin area.

“This has been an accident waiting to happen,’’ said Dr. Thomas Treadwell, director of the infectious disease clinic at MetroWest Medical Center in Framingham. “If you don’t have the deer, you don’t have the tick. And if you don’t have the tick, you don’t have the disease. But we now have the perfect habitat here.’’

Doctors who treat patients and specialists who track ticks said they’re convinced the rise in cases — last year, there were 4,042 statewide, compared with 1,194 in 2000 — reflects a genuine increase in illness and not simply better diagnosis or recordkeeping. The increase is too large to be explained by better surveillance, specialists said: In Middlesex County, for example, there were 136 cases in 2000, and by 2008, diagnoses had soared to 767.

Source: Boston Globe