Ehrlichiosis: Wisconsin Data
The number of reported cases of ehrlichiosis has been increasing in Wisconsin.
In 2020, Wisconsin had 17 probable and confirmed cases of ehrlichiosis.
Several species of Ehrlichia bacteria cause ehrlichiosis. In Wisconsin, species of Ehrlichia that can cause illness include:
- Ehrlichia chaffeensis
- Ehrlichia muris eauclairensis
- Ehrlichia ewingii
Ehrlichiosis is preventable and treatable. Learn more about Tick Bite Prevention.
Read about Signs and Symptoms from the CDC (Centers for Disease Control and Prevention).
The graphs below show statewide data for ehrlichiosis.
For national data, visit the CDC webpage on Ehrlichiosis Epidemiology and Statistics.
Ehrlichiosis data
In the past, ehrlichiosis surveillance included human granulocytic ehrlichiosis and human monocytic ehrlichiosis. As of 2008, the surveillance case definition changed to classify the disease by two different bacterial infections: Anaplasma phagocytophilum and Ehrlichia species.
Ehrlichiosis cases in Wisconsin
Three species of Ehrlichia cause illness in Wisconsin and other parts of the United States: E. chaffeensis, E. muris eauclairensis, and E. ewingii.
E. muris eauclairensis is a newer species of Ehrlichia. It was discovered in Wisconsin and Minnesota in 2009.
E. ewingii is rare in Wisconsin. There have been two reported cases in the state.
Ehrlichiosis cases reported by month and age
Contact us
Questions about illnesses spread by ticks? We’re here to help.
Bureau of Communicable Diseases
Phone: 608-267-9003
Fax: 608-261-4976