Anaplasmosis: Wisconsin Data

Anaplasmosis is the second most common illness spread by ticks in Wisconsin, after Lyme disease.

From 2015 through 2024, Wisconsin had an average of 565 confirmed and probable cases of anaplasmosis reported per year.

In 2024, a total of 780 confirmed and probable cases of anaplasmosis were reported.

Cases were most commonly reported among people living in the northern, western, and northeastern regions of the state.

Anaplasmosis is preventable and treatable. Learn more about Tick Bite Prevention.

Read about Treatment and Signs and Symptoms from the CDC (Centers for Disease Control and Prevention).

The map and graphs on this page show statewide data for anaplasmosis.

For national data, visit the CDC webpage on Anaplasmosis Epidemiology and Statistics.

Map of Anaplasmosis incidence by county in Wisconsin

Anaplasmosis data

Chart showing anaplasmosis cases in Wisconsin. The number of cases peaked at 780 in 2024

Chart showing the average anaplasmosis cases by month from 2015-2024. Cases are most common in June and July in Wisconsin

Chart showing the average Anaplasmosis Cases by Age Group from 2015 to 2024. The age group with the highest number of cases is age 65-69

Learn more about anaplasmosis

Questions about illnesses spread by ticks? Contact us!

Phone: 608-267-9003 | Fax: 608-261-4976

Glossary

 
Last revised October 3, 2025