Michigan Confirms Human Eastern Equine Encephalitis Case

Last week, the Michigan Department of Health and Human Services confirmed a locally acquired case of eastern equine encephalitis (EEE) in a Roscommon County resident. This is the first EEE human case of the mosquito-borne disease reported in Michigan since 2021.

State and local health departments, along with the Michigan Department of Agriculture and Rural Development and the Michigan Department of Natural Resources, have been monitoring and will continue to monitor for signs of EEE in humans, mosquitos, domestic animals and wildlife. Prior to this case, no animal EEE activity has been detected in Michigan this year. Additional mosquito trapping and testing is underway in Roscommon County to assess the level of risk in the area. Information about human, animal and mosquito pool testing is available in a weekly arboviral report.

“It is vital that Michigan residents take precautions against mosquito bites as mosquitoes can carry diseases that can have devastating health effects,” said Dr. Natasha Bagdasarian, chief medical executive. “EEE is one of the most dangerous mosquito-borne diseases in the U.S., with a 30% fatality rate among people who become ill.”

EEE virus is spread to people by the bite of an infected mosquito. EEE is a rare but serious disease. Only a few human cases are reported each year in the United States.  People who become ill with EEE may experience fever, headache, chills and nausea. In some cases, symptoms may progress to inflammation of the brain, signaled by disorientation, seizures and coma. Physicians treating patients with these symptoms should consider testing for EEE and other mosquito-borne viruses and report suspect cases to their local health department. The MDHHS Bureau of Laboratories offers comprehensive testing for the arboviruses of concern in Michigan.

Also, this month, Michigan health officials identified a human case of influenza A H1N2 variant (swine flu) in an Ionia County resident who was a swine exhibitor at the Kent County Youth Fair. The fair took place Aug. 3-8 at the Grand Agricultural Center of West Michigan in Lowell. County health officials reached out to swine exhibitors and their families who visited the swine barns at the Kent County Youth Fair to identify any additional illnesses in those who may have been exposed to influenza from infected pigs.

Additionally, Michigan’s health department on Aug. 20 reported 14,277 cases linked to ‌an ongoing cyclosporiasis outbreak. Michigan has been the state hardest hit by the multistate outbreak of the ​parasitic illness, reporting two related deaths, both in people with significant underlying health conditions.