By Erica Kritt, Times Staff Writer

Lyme disease is on the rise in Maryland, but state officials say they cannot be certain it is because of an increase in ticks.

The latest statistics show that the number of Lyme disease cases more than doubled from 2006 to 2007.

S.B. Wee, chief of the Maryland division of zoonotic diseases, said a number of factors could be contributing to the increase.

Wee said both physicians and residents are more aware of the disease.

“People know to ask their doctors,” she said.

She also said that health departments are following up more on reports of tick bites.

Lyme disease is the most common tick-borne infectious disease in the country. It is transmitted to humans by the bite of a black-legged tick infected by the Borrelia burgdorferi bacterium.

A tick must be attached to the skin for at least 24 hours for the transmission to occur, according to the Maryland Department of Health and Mental Hygiene.

In Carroll County, the incidence of Lyme disease increased by 55 cases, from 197 in 2006 to 252 in 2007.

Queen Anne’s, St. Mary’s and Talbot counties were the only jurisdictions that saw a decrease in Lyme disease.

Doris Hare, director of communicable diseases at the Carroll County Health Department, said Maryland is one of 10 states that have the most exposure.

According to a Centers for Disease Control and Prevention map, the majority of cases are along the northeast coast, from Maine to Virginia.

Hare said Carroll happens to be an area with tall grass, trees and deer, all places where ticks live.

Hare said there used to be a vaccine for the disease, but it was pulled from the market.

According to the American Lyme Disease Foundation, the vaccine was approved by the Food and Drug Administration in 1998, but citing low demand, the vaccine was taken off the market by GlaxoSmithKline in 2002. The vaccine was not long-lasting, and those who received the vaccine are no longer protected from the disease.

Hare said being aware of your surroundings and the symptoms of Lyme disease is the best way to prevent it.

“You need to check yourself,” she said. “If you have symptoms, if you have a bull’s-eye rash, you need to call your doctor.”

According to DHMH, 70 percent to 80 percent of people infected will have a gradually expanding rash three to 30 days after a bite.

Hare said there is a misconception that you have to be hiking or in very woodsy areas to encounter ticks.

“Ticks can be in your backyard,” she said.

Hare said there may be more cases of ticks this time of year because people are starting to go outside more as the weather gets warmer.

According to DHMH, ticks are most active from late spring to early fall.

“We might have higher incidences because we didn’t have a very cold winter,” Hare said.

Reach staff writer Erica Kritt at 410-857-7876 or This e-mail address is being protected from spambots. You need JavaScript enabled to view it .