Your Body Almanac

Wisconsin

Lyme ticks in every county, nitrate in some wells, and long dark winters.

Wisconsin is a high-incidence Lyme disease state, and the ticks that spread it live in every county. Nitrate is common in its groundwater, much of the south is in EPA's highest radon zone, and winters are long, cold and low on sun.

01

Ticks and Lyme disease

Lyme disease is the most common tickborne illness in Wisconsin, and the ticks that spread it have been found in every county. Blacklegged ticks live in woods, brush and leaf litter. Untreated Lyme can affect joints, the heart and nerves.

SourcesLyme Disease (Wisconsin Department of Health Services)Surveillance for Lyme Disease After Implementation of a Revised Case Definition — United States, 2022 (CDC MMWR)
Check for ticksAs neededAfter time in grass or woods, check your whole body, shower within two hours and dry your clothes on high heat. Use insect repellentAs neededUse an EPA-registered repellent on exposed skin when mosquitoes or ticks are around.
02

Nitrate in private well water

Nitrate from fertilizer and animal waste is one of the most common groundwater contaminants in Wisconsin, and studies estimate at least 10 percent of private wells have high levels. It is a particular risk for babies and during pregnancy. The state health department suggests testing your well for nitrate every year.

SourcesDrinking Water: Nitrate and Nitrite (Wisconsin Department of Health Services)
Test your private well every yearYearlyIf your water comes from a private well, have it tested by a certified lab at least once a year.
03

Radon in many homes

Radon is an invisible, odorless radioactive gas that seeps from soil into homes and is the leading cause of lung cancer in people who don't smoke. EPA's map puts much of southern Wisconsin and several central counties in Zone 1, its highest-risk category. Testing is the only way to know your home's level.

SourcesWisconsin — EPA Map of Radon Zones (EPA)Radon (Wisconsin Department of Health Services)
Test your home for radonAs neededRadon is invisible and odorless, so a simple test is the only way to know your level. Fix it at 4 pCi/L or higher.
04

Little winter sun for vitamin D

Your skin makes vitamin D from the sun's UVB rays. A classic study found that winter sunlight in Boston, at 42 degrees north, made no vitamin D in skin from November through February. Wisconsin lies north of that, so through the winter food is the more reliable source.

SourcesVitamin D — Health Professional Fact Sheet (NIH ODS)Influence of season and latitude on the cutaneous synthesis of vitamin D3 (Webb et al., 1988, PubMed)
Get vitamin D from foodDailyEat fatty fish, fortified milk and UV-exposed mushrooms so you are not relying on the sun alone. Ask your doctor about vitamin DYearlyIf you get little sun or few vitamin D foods, ask at your checkup whether testing or a supplement makes sense for you.

When to see a professional

See a doctor for an expanding rash, fever, facial droop or joint swelling after a tick bite. If you are pregnant or have a baby and drink well water, ask about nitrate testing. Get care for numb, hard or waxy-looking skin after cold exposure.