Information On Lyme Disease Increasing: Massachusetts
Threat of Lyme disease widens
Number of cases jumps in counties farther inland
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, specialists 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 flu-like symptoms but in some cases causes serious cardiac and neurological 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 record keeping. 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.
Bruce Moran knows all too well the consequences of Lyme disease's spread.
He was on his hands and knees behind his Charlton house a couple of months back, plucking stray vegetation from around a deck. Deer had ventured there, too; their telltale nibbles pocked the unkempt growth.
Several nights later, he awakened, feeling sick. Before long, his temperature flared to 104 degrees. Initial blood tests found no evidence of Lyme disease, but that's not unusual...
"They tell me that years ago, if you dragged for ticks along the street in Newton, you wouldn't find any," said Dr. Alfred DeMaria, top disease tracker at the Department of Public Health. "But you find them now.''
And they're in places like Newton because deer are there.
The deer population has increased steadily in recent decades, according to the Massachusetts Audubon Society. Areas that once were denuded for agricultural and industrial purposes are flush with foliage again, luring wildlife. And when suburban development edges into those wooded areas, the resulting fragmented forests remain a favorite haunt for white-tailed deer — and for a mouse that is a pivotal actor in the Lyme disease-transmission cycle.
"The white-footed mouse retains the infection and transmits the disease back to ticks," said entomologist Dave Simser...
"Because it's only going to get worse,'' said Dr. Sam Telford, an epidemiologist at the Cummings School of Veterinary Medicine at Tufts University. "We've predicted that the corridor between [Route] 128 and [Interstate] 495 will become the next Cape and Islands.''