From 1996 to 2013, 374 cases of babesiosis were reported in Minnesota. In 2013, 64 confirmed and probable babesiosis cases (1.2 per 100,000 population) were reported, the second highest total since 2011’s record of 72 cases. Yearly case totals since 2005 (range, 10-72) have been consistently higher than reported totals from 1996 to 2004 (range, 0-9).
The number of babesiosis cases has been increasing since it first became reportable in the mid-1990s. A variety of factors, including increasing physician awareness, increasing infection rates in ticks, and expanding tick distribution may have led to this trend.
Cases of babesiosis in 2013 ranged in age from 4 to 89 years; the median age (66 years) was greater than that of Lyme disease (42 years). In 2013, 58% of babesiosis cases were male. Onsets of illness peaked in the summer months, with 43 (69%) of 62 cases with known onset occurring from June through August. At least 3 reported cases died from complications of babesiosis in 2013.
- Reported Cases of Babesiosis in Minnesota
by Year, 1996-2013 (PDF: 104KB/1 page)
Graph showing the number of reported cases of Babesiosis in Minnesota by year.
- Reported Cases of Babesiosis in Minnesota by Month of Onset 1996-2013 (PDF: 103KB/1 page)
This bar graph shows reported cases of Babesiosis by the month of onset.
Most babesiosis cases report likely exposure to blacklegged ticks in the same east-central,north-central, and southeast Minnesota counties where the risk of Lyme disease is greatest.
- High Risk Areas for Tick-borne Diseases in Minnesota
A map that shows counties of highest tick-borne disease risk in Minnesota.