The federal Environmental Protection Agency has linked increasing cases of Lyme disease to climate change.

The EPA has charted the rate of reported Lyme disease cases and found that the number of cases per 100,000 people has more than doubled in the last 25 years.

In 1991, there were fewer than four cases of Lyme disease per 100,000 people. That number jumped to almost eight last year. EPA’s chart shows a steady upward trend of cases reported by local and state health departments.

The EPA says that 20,000 to 30,000 cases are being reported each year, but the number of actual cases is likely higher.

While noting that climate is not the only factor affecting the spread of ticks which carry Lyme disease, the EPA wrote “studies provide evidence that climate change has contributed to the expanded range of ticks, increasing the potential risk of Lyme disease, such as in areas of Canada where the ticks were previously unable to survive.

“Warming temperatures associated with climate change are projected to increase the range of suitable tick habitat and are therefore one of multiple factors driving the observed spread of Lyme disease,” the EPA said. “Because tick activity depends on temperatures being above a certain minimum, shorter winters could also extend the period when ticks are active each year, increasing the time that humans could be exposed to Lyme disease.”

Lyme disease is transmitted largely by ticks, although ticks can also carry other vector-borne diseases as well. Lyme disease often manifests itself with flu-like symptoms and joint pain. It can also cause neurological issues, fatigue, heart problems and liver inflammation.

Lyme disease was not an issue in the northern Adirondacks until fairly recently. But during a recent community lecture series, Dr. Jonathan Krant, who is a rheumatologist with Adirondack Health, has said changes in long-term weather patterns brought an increase in both ticks and Lyme disease to the area.

He said Keene and Keene Valley have become an epicenter of the disease in the Adirondacks.

Krant said at a lecture in June at the Saranac Lake Free Library that outdoors recreators need to take precautions against getting bitten by a tick. He also said that local doctors need to be more vigilant in looking for the disease.

Krant said that blood tests for the disease can come back negative early on, and the downside of treatment is very minimal.

“Don’t withhold therapy just because they don’t have a rash or a history of an attached tick. Ticks evade surveillance,” he said. “They’re nature at its best.”

“And for those physicians who say that Lyme disease doesn’t exist in the Adirondacks, they’re out of their minds. We have unequivocal data” that shows the disease is present here.

Krant added that the iconic “bullseye” rash often associated with Lyme disease is actually present in fewer than half of all cases.

Ticks can transmit the disease through biting, so it’s important for outdoors users to check themselves for the little eight-legged creatures.

Wearing light-colored clothing with a tight knit can help people find the ticks before they become engorged.

And removing a tick is critical, as long as the whole tick, and not just the body, are removed. A tick’s head and mouth parts, if left attached, can still transmit the disease.

“I don’t care how you do it, just get them off your body, and do it so the mouth parts aren’t embedded,” Krant said. “That’s where the action is, and it can still be transmitted even if the body and thorax are removed.”