Lyme disease is increasing

Lyme disease data now available on Data Access portal

Lyme disease is becoming more common in Minnesota. Minnesota is one of 14 states that has the majority of Lyme diseases cases in the country. The number varies from year to year, but the overall trend shows an increase in Lyme disease in Minnesota since 2000.
Not only are the number of cases increasing, but the geographic distribution is increasing, expanding north and west of traditional risk areas in Minnesota.
View data on Lyme disease trends, seasonality, age and sex of patients, symptoms, and geographic distribution at MN Public Health Data Access: Lyme Disease. You can use these data for Lyme disease awareness and prevention efforts.

Minnesota Department of Health
Minnesota Public Health Data Access is updated and maintained by the MN Environmental Public Health Tracking Program, part of the CDC's National Tracking Network.
 

Ticks in Minnesota
 
Ticks carry disease, and the start and length of tick 'season' in Minnesota can vary with the the weather seen in late winter/early spring.  Warmer weather leads to earlier than normal tick activity and a sudden start to the tick-borne disease season.
 
Blacklegged ticks, often called the "deer ticks," feed across the forested regions of Minnesota. This type of tick carries the agents of several diseases, including Lyme disease, human anaplasmosis, babesiosis, Powassan disease, and a new form of human ehrlichiosis. Over the last decade, 1,000 to 2,000 or more combined cases of these tick-borne diseases each year have been reported to the Minnesota Department of Health, with these numbers increasing in recent years.
 
The risk for diseases from blacklegged ticks in Minnesota usually starts to rise in late spring and stays elevated until mid-summer, with a smaller peak again in autumn.  Blacklegged ticks carry most of Minnesota’s tick-borne diseases.  In addition, American dog ticks (“wood ticks”), which are very common in spring and early summer throughout Minnesota, can carry Rocky Mountain spotted fever (RMSF). While RMSF is most common in the southern United States, a small number of RMSF cases, including one death, have occurred in Minnesotans who did not travel outside the state.
 
The best way to prevent tick bites is to avoid tick habitat during warm weather months:
  • Wooded or brushy areas for the blacklegged tick
  • Grassy or wooded areas for the American dog tick
If you can’t avoid tick habitat, use repellent to reduce the risk of disease:
  • DEET based repellents (up to 30 percent DEET), which can be applied to clothing or skin for temporary protection
  • Permethrin based repellents, which are used to pre-treat fabric and can protect against tick bites for at least two weeks without reapplication
People who live on heavily wooded property, whether permanent homes or cabins, often encounter ticks on a daily basis. Since daily repellent use can be more challenging for these people, they should consider the following landscape management techniques:
  • To make your yard less attractive to ticks:
    • Keep lawns mowed short
    • Remove leaves and brush
    • Create a landscape barrier of wood chips or rocks between mowed lawns and woods
  • To reduce tick numbers where your yard and the woods meet:

Early detection of tick-borne illness is important to prevent severe complications, so people should seek medical care if they develop an illness suggestive of a tick-borne disease after spending time in tick habitat. Signs and symptoms of the various tick-borne diseases can include, but are not limited to, rash, fever, headache, fatigue, muscle aches, joint pain or swelling, and facial droop. These symptoms can also be involved in other diseases, so it is important for a patient's medical provider to consider tick-borne and non-tick-borne causes. Fatal cases of tick-borne disease occur each year in Minnesota residents. Except for Powassan disease, which is caused by a virus, all of Minnesota's tick-borne diseases are treatable with antibiotics.

More information about Minnesota's tick-borne diseases, including signs, symptoms, and prevention, is available on the MDH website http://www.health.state.mn.us/divs/idepc/dtopics/tickborne/index.html