It was believed that deer ticks which can carry Lyme disease, are primarily found in the woods of the lake areas of central Minnesota. But they seem to travelling into more populated areas.
This change in the deer ticks' venue was first noticed in 2007, again in 2008 and 2009, as they have headed further east and northeast. Speculation as to the reasons for this are twofold: woods and residential areas are not so far apart as they were in the past, and relatively mild winters in the past few years have made the ticks' survival easier.
"Since 2004, the Health Department has counted an average of about 1,000 cases of Lyme disease statewide each year, twice the average annual number from 1999 to 2003. Cases of anaplasmosis and babesiosis, also transmitted by ticks, have risen sharply, as well, to about 300 anaplasmosis and 30 babesiosis cases in each of the past three years. And the first three cases of Powassan encephalitis ever reported in Minnesota occurred in the past two years. Minnesota has also seen its first cases of Rocky Mountain spotted fever in recent years."