Now that the area ticks call home is expanding, the risk of getting Lyme disease isn't limited to those who live up north -- and the FOX 9 Investigators found out that means the dangerous illness is under-diagnosed because the symptoms can mimic other illnesses and tests can be inconclusive.
For years, the Minnesota Department of Health has tracked hot zones, where the risk of running across an infected tick is the highest. For the most part, the metro has been spared, but officials have found black-legged ticks, also known as the deer tick, in all seven metro counties in recent years.
Ross Savage lives in the heart of Minneapolis. He doesn't frequent any of the known tick hot zones outside the metro, but he still found himself fighting Lyme disease.
"It's hard to see those ticks all the time -- especially when you're not looking for them because you're here in town and you don't feel like it's something you're going to be threatened by," said Savage.
The symptoms for Lyme disease, which is the most common tick-borne illness, include headaches, muscle aches, joint aches and fatigue. That means it can easily be mistaken for something else.
"I began to have paralysis in my left side," recalled Karri Piecora, who lives in the metro area. "We went to many different doctors. They thought I had M.S., lupus."
Piecora's illness started with an excruciating headache. In fact, she said the pain was so intense that she thought she was going to die.
"I would get where I couldn't walk and then I couldn't speak," she said.
To this day, she still has some paralysis in her lip, but weekly injections of antibiotics are helping.
Doctors were stumped by her case at first. Two blood tests for Lyme disease came back negative before a third confirmed the infection many months later.
"We do have a tendency, I believe, to under-diagnose Lyme disease," said Dr. Betty Maloney, who teaches other doctors about the tick-borne illness.
When asked why, Maloney said she thinks Lyme disease gets missed because not all cases look the same. In fact, the characteristic rash that usually follows a tick bite is absent in about 30 percent of Lyme disease patients.
As Piecora discovered, blood tests aren't a sure thing either. In fact, Maloney says you could take 100 people with Lyme disease, and a sizable number of the tests might come back negative.
"Ultimately, at the end of the day, you would have told 56 percent of the 100 they had Lyme disease, but you would have told 44 that they didn't (have it)," said Maloney.
A record number of Minnesotans got sick from tick bites last year. Nearly 1,300 cases of Lyme disease were reported, and about a third of the patients were children.
The black-legged tick dines on deer to help it thrive, but that doesn't mean deer need to live in an area where ticks can be found.
"When the female tick lays her eggs on the forest floor, she'll lay like, 1-3,000 eggs all in the same spot," said Dave Neitzel, with the Minnesota Department of Health.
The ticks are born without disease, but the young ones get infected by feeding on mice and other small animals which can carry the harmful germs that make people sick. If you see chipmunks and other rodents scurrying around your property, there could be ticks on them also.
However, ticks can't jump over to get on us. Humans need to make physical contact with them in order to get bitten. Once a tick grabs hold of you, it needs to stay attached for a least a day to inject the bad bacteria.
University of Minnesota researchers are studying how these germs act once they invade the body -- but until a vaccine comes along, the best line of defense against any tick-borne disease is to be careful where you walk.
Experts recommend walking on trails in wooded areas. In fact, Neitzel said walking in the center of a paved trail will give you no risk of picking up ticks. Instead, those off-trail moments into the brush are when ticks can come in contact with -- and attach to -- passerby.