The first report of a black-legged tick (deer tick) out and feeding in Minnesota this year came April 6, said David Neitzel, a specialist on tick- and mosquito-borne illnesses for the Minnesota Department of Health (MDH).
These tiny ticks, which can be as small as a freckle, are carriers of several illnesses, and Cass and Crow Wing are two of the state’s counties that are at highest risk of diseases like Lyme, human anaplasmosis, babesiosis, ehrlichiosis and powassan.
Neitzel said that rather than hindering the tick population, chances are the thick layer of snow the area received this winter provided insulation for the ticks, which winter in rotting leaf litter on the forest floor.
“When the snow melts and the ground temps get around 50 degrees, the ticks start moving,” Neitzel said.
The only sort of winter that would reduce the tick population would be one with little snow and extremely cold temperatures, he said.
The height of tick season, Neitzel said, is mid-May to mid-July. This is the time when primarily nymphs are out feeding. Nymphs are ticks in an early stage of life.
“They’re extremely small, one millimeter in length, and because of that people are bitten and don’t even know,” Neitzel said.
Neitzel said that one in five nymphs carries Lyme disease, while one in three adult black-legged ticks carries the disease.
“The risks are fairly high. If you have three ticks, there’s a good chance one is infected,” Neitzel said. However, in order for Lyme disease to be transmitted from the tick, the tick has to be attached for a day or two. This is the case with most tick-borne illnesses, Neitzel said.
Except for powassan. While it’s one of the more rare tick-borne illnesses, Neitzel said there is evidence this disease, because it’s a virus rather than a bacteria, could be transmitted within 20 minutes of a tick biting in.
While there were only 11 reported cases of powassan in Minnesota in 2011 (the latest data MDH has), one of them resulted in death in Cass County, said Lynne Jaycox, a public health nurse for Crow Wing County.
Incidents of powassan, babesiosis and anaplasmosis were all up in 2011, Jaycox said.
“One of our main messages is that we have a lot more than just Lyme disease out there, and the same ticks that transmit Lyme can transmit agents of four others that we know of,” Neitzel said. “Crow Wing County has been at the heart of our tick-borne disease area since we learned about tick-borne diseases in the 1980s.”
Since then, high risk areas have spread north to Cass County.
The risk of tick bites is greatest in the woods.
“Even at the heart of a high-risk area, if you get right in town, ticks are going to be pretty rare,” Neitzel said.
Ticks don’t jump or drop from trees; they live on the ground and crawl upward to bite. For that reason, Neitzel suggested that people focus prevention on the lower half of their bodies.
Jamie Richter, public nurse for Cass County, said oftentimes early symptoms of tick-borne illness include the bull’s-eye rash, redness at the site of the bite, headache, fever, chills, fatigue and simply not feeling well.
Richter stressed the importance of preventing all vector-borne diseases, not just those from ticks. Mosquitoes also pose a threat because of West Nile virus. While the incidents of West Nile are much lower than those of tick-borne illness, the risk is still there.
Richter, Neitzel and Jaycox all said it’s important people protect themselves by checking for ticks often and using a repellant with DEET at up to 30 percent or with permethrin.
Permethrin should be sprayed on clothing. Neitzel said the permethrin stays on clothing through two or three washes and will kill the ticks it contacts.
Jaycox said that when someone gets a tick, the best practice for removal is not with Vaseline or burning, as some might think, but simply with a tweezers, grabbing close to the head and pulling back slowly and steadily. Then, she said, apply a little antibiotic ointment.