Sometime earlier this year, a Wilkes County resident was bitten by a tick. In late June, the resident died, a victim of the tick-borne illness Rocky Mountain spotted fever.

The incident highlights the need for North Carolina residents to be vigilant as cases of tick-borne illnesses continue to rise, public health officials cautioned.

"We typically vie for the most cases of RMSF with Oklahoma," said Dr. Edward Breitschwerdt, professor of medicine and infectious diseases at N.C. State University's veterinary school. "The number of reported cases has definitely been increasing."

The reason North Carolina is near the top of the country in Rocky Mountain spotted fever cases is unclear. According to the state epidemiologist, Dr. Jeff Engel, it's unlikely that the number of disease-toting ticks has changed suddenly.

"The locals have always known about ticks," he said. "As a matter of fact, there's a town in Lenoir County called Tick Bite."

Engel pointed to land development as one reason for the increase. As suburbs expand into what was once tick habitat, human-tick interaction increases.

But the severity of the tick problem has proved difficult to quantify. Tick populations can be spotty and hard to test, Engel explained.

"There could be a tick population on one side of the road that carries an illness, and on the other side of the road one that doesn't," he said. Still, Engel doesn't rule out the possibility that the tick population is growing.

"There have been conjectures about ecological changes that could lead to that," he said. A decline in the population of predators such as grouse and quail could be contributing to the problem, he added, as well as an explosion in the deer population -- a favorite host of the parasite.

Whatever the cause, the incidence of tick-borne illnesses has risen significantly over the past decade. From 1998 to 2002, the annual average of Rocky Mountain spotted fever cases was reported at 156. During the period from 2002 to 2006, the number more than doubled, with 527 reported cases per year on average, according to the state Division of Public Health.

The statistics for Lyme disease, a tick-borne illness well known in the Northeast but thought until recently not to exist in North Carolina, are lower than those for Rocky Mountain spotted fever. Fifty-three cases were reported in the state last year.

But some residents don't trust these statistics.

"I guarantee you the numbers aren't right," said Beth Jordan, a veterinarian and founder of the North Carolina Lyme Disease Foundation. "The doctors are afraid to diagnose Lyme disease because they'd feel compelled to treat it, and the medical board doesn't approve of the treatment."

Jordan referred to a case in 2006 involving a Charlotte doctor, Joseph Jemsek, who was disciplined by the N.C. Medical Board for deviating from the standards of Lyme diagnosis and treatment as recognized by the state.

Patients suffering from the symptoms of chronic Lyme disease or other Lyme-related illnesses contend that the state's medical establishment downplays the reality of their condition. Some, such as Lyme activist and pilot David Tierney of Cary, are outraged by the state's refusal to recognize their complaints.

"What floors me is that the state isn't doing any education on ticks," said Tierney, whose symptoms of chronic Lyme disease were misdiagnosed for months as multiple sclerosis. "The state doesn't want to admit that there's a tick problem. They don't want to admit that there's Lyme. If the state doesn't accept it, doctors won't see you."

Engel insisted the state was not ignoring the issue.

"We have Lyme disease in the state," Engel said, "and we are currently doing tick-collection studies to determine how bad the problem is."