The Wisconsin Department of Health Services and the Chippewa County Health Department have announced that laboratory testing has confirmed a case of eastern equine encephalitis virus infection in a woman in her 60s who had been living in Chippewa County. This is the second human case of EEE in state so far this year and the first resulting in a death.

“We are very sad to report that one of our fellow Wisconsinites has contracted EEE and has passed away. This is the second confirmed case of EEE in our state this year and the seriousness of this infection cannot be overstated,” cautioned Interim State Health Officer Stephanie Smiley. “Since mosquitoes continue to be active in Wisconsin, we are urging people to continue to take steps to protect themselves from mosquito bites.”

There have also been nine cases of EEE reported in horses this year; all of which were in the northwestern part of the state, and four of those from Chippewa County. These cases in animals and now in two residents of the state represent unusually high levels of EEE activity in the state.

EEE virus is a rare, but potentially fatal disease that can affect people of all ages. Symptoms begin anywhere from three to ten days after the bite of an infected mosquito. Inflammation and swelling of the brain, called encephalitis, is the most dangerous and frequent serious complication. In Wisconsin, the last human case of EEE was reported in 2017.

EEE can be spread to humans through the bite of an infected mosquito. Mosquitoes acquire EEE virus by feeding on infected birds. The virus is not spread person to person or directly between animals and humans.

Even though temperatures have cooled off, as long as mosquitoes are active, the risk of EEE and other illnesses spread by mosquitoes can continue through much of the fall. The single best prevention tool continues to be avoiding mosquito bites.

DHS and the Chippewa County Health Department encourage all residents to take precautions against being bit by mosquitoes. For more information on preventing mosquito bites, visit www.dhs.wisconsin.gov/mosquito/bite-prevention.htm.