In Indiana, the number of Lyme disease cases has increased 82 percent, rising from 34 cases in 2005 to 62 in 2009, according to the Indiana State Department of Health.
In Tippecanoe County, the number of cases investigated by public health nurses rose 90 percent from 1 case in 2005 to 10 in 2010, according to the county health department.
The cause for the increase is unknown. Possible theories range from an upswing in the number of cases reported to a higher percentage of ticks that are infected with the bacterium, according to health officials.
Northwest Indiana also saw a possible surge in Lyme disease cases. The Associated Press recently reported that nearly 18 people said they had the disease at a town hall meeting in Ogden Dunes, a northwestern Indiana town along Lake Michigan.
Gibb said that a surge in that area is not surprising. "Within Indiana we find it most in the northwest," he said. "That whole area (northwest Indiana, northeast Illinois and southern Wisconsin) has been traditionally a hot spot for deer; as a result deer ticks and as a result of that Lyme disease."
The black-legged tick is most likely being transported south and east within the state on the backs of deer - its preferred host, especially as the deer population increases, Gibb said.