Mike Lee knew about the dangers of ticks and Lyme disease, so he took precautions before heading into the woods last August near Lake Mille Lacs. "I sprayed repellent on my clothes and tucked my pants inside my boots," said Lee, 34, of Isle, Minn. Lee is a Department of Natural Resources conservation officer who was helping sheriff's deputies investigate a marijuana patch in a state wildlife area.

Despite his attentiveness, when he got home, Lee found a small black tick stuck on his thigh. The tick had been there only a few hours, so he wasn't concerned. And there was no rash, which might indicate Lyme disease.

Three days later, he was driving on vacation to Missouri when he felt sick. "I've never been so sick in my life," he said. He stayed in bed several days, then, running a fever of 103 degrees, he got up to take a shower. "I looked down and noticed the spot where the tick bit me was black, the size of my fist. And when I urinated, it was the color of maple syrup."

Lee was subsequently diagnosed as having Lyme disease, one of about 1,043 cases reported in Minnesota in 2008 -- the second-highest tally since health officials began tracking the disease in 1986. A record 1,239 cases were found in 2007, but the state has averaged more than 1,000 the past five years -- a dramatic increase from a decade earlier, when the state averaged 235 cases a year.

Now, in August, as many Minnesota families begin vacations, and with fall hunting seasons in the offing, adult blacklegged ticks renew their threat. "The adult ticks come out to feed in fall and spring," said Dave Neitzel, a Minnesota Department of Health epidemiologist.

The adults replace -- or supplant -- the risk that 2-year-old blacklegged ticks pose in their nymph stage from mid-May to mid-July.

A report last week that two other serious tick-borne diseases have surfaced in Minnesota -- Rocky Mountain spotted fever and Powassan encephalitis -- underscores the health threat ticks pose. Human anaplasmosis is another disease spread by ticks that has infected more than 1,500 people in Minnesota since 1995, including 278 last year.

But Lyme disease is by far the No. 1 tick-borne risk Minnesotans face.

"The last few years have been real intense for Lyme disease transmission in Minnesota," Neitzel said. More doctors might be aware of the disease and are diagnosing it, he said. Also, infection rates in blacklegged ticks -- the primary carrier of the disease -- are increasing, and the ticks have expanded their range.

Ticks found in new areas

"We're finding blacklegged ticks in some areas where they had not been reported before," Neitzel said. He expects them to continue to spread in central and northern Minnesota -- bad news for grouse and deer hunters, hikers, campers and others who visit the woods.

"Lots of folks bird-hunting will come across ticks in pretty good numbers," he said. "Usually by the opener of deer hunting [in November], the ticks are beginning to decline, but with recent warmer openers, hunters have reported lots of ticks on themselves and on the deer."

Lee said he recently dealt with a black bear that had been struck and killed by a vehicle on a highway. "It was just covered with ticks," he said.

"I was pulling it off the road, and there were ticks running up my arms."

Risks unknown

Early-season deer hunters in Lee's area -- near Mille Lacs -- often find deer with many ticks. "They need to take precautions when they're cleaning them," he advised. "And they should make sure they check themselves afterward."

Neitzel said officials aren't sure what the chances are of Minnesotans getting Lyme, because no one knows what percentage of people who travel in the woods become infected.

"If you're someone who gets out into woods and brush, your risks will be much higher," Neitzel said. He said that outdoor enthusiasts shouldn't be afraid to go into the woods because of the threat of Lyme disease, but that they should take proper precautions.

"We really stress the use of repellents. Repellents with DEET are very effective, but for people who spend a lot of time in the woods, we recommend permethrin, which is used only on clothing. It's very effective."

Long-sleeve shirts and pants, with the pants tucked into boots, also help, as does light-colored clothing, so that ticks can be seen easier. But as Lee's case underscores, there are no guarantees. He followed the recommendations.

"I don't know how that tick got on me," he said. "I couldn't believe it. Usually they crawl up from the ground."

Equally perplexing is the that he found the tick early and removed it. The state health department and other sources say that a blacklegged tick must be attached to a person at least 24 hours before it transmits Lyme disease. But Lee said that wasn't the case with him. "It was only on me for six or seven hours," he said.

Living with Lyme

Lee said his experience with Lyme disease was a nightmare that has had a lasting impact on him and his family. He's not only in the woods for his job, he also hunts and fishes.

He lives with his wife and four young children near Isle, an area that is heavily infested with ticks.

"I worry about it every time I go out in the woods," he said. "I'm way more cognizant of checking myself for ticks all the time. I've encountered quite a few deer ticks this year. I haven't had any stuck to me, but I've had them crawling on me."

His kids often play in the woods outside his house.

"I'm paranoid about it with my kids. We spray their clothes, and we check them every time they come in [from outside]. We don't want them getting infected."

Meanwhile, nearly a year later, Lee goes to his doctor for regular checkups, and wonders whether there will be long-term health effects.

"All from a little tick," he said.

Doug Smith • 612-673-7667