A Wayne County resident has been diagnosed with the year’s first case of West Nile virus in Michigan.

The Michigan Department of Health and Human Services on Thursday confirmed the case and warned that the potentially deadly mosquito-borne disease Eastern Equine Encephalitis, or EEE, is circulating in the state with 13 confirmed cases in horses in Barry, Clare, Kent, Montcalm, Newaygo and Oakland counties. 

The year's first case of West Nile virus, a disease carried by mosquitoes, has been diagnosed in Wayne County, health officials said.

“It only takes one bite from an infected mosquito to cause a severe illness, so take extra care during peak mosquito-biting hours, which are dusk and dawn for the mosquitoes that transmit West Nile virus and Eastern Equine encephalitis virus,” said Joneigh Khaldun, chief medical executive and chief deputy for health at MDHHS, in a statement. 

State veterinarian Nora Wineland urged animal owners to ensure their pets are vaccinated, saying “we can’t let our guard down.”

Michigan last year experienced the worst outbreak of EEE ever recorded, with 10 human cases, including six deaths and 50 cases in animals statewide.

Between Sept. 28 and Oct. 10, 2019, more than 557,000 acres in Michigan were treated with aerial applications of insecticide to kill infected mosquitoes.  

Two birds from Lapeer and Oakland counties have tested positive for West Nile. Infected birds, animals and mosquitoes in a community is an indication of risk for human infection, the state said.

In addition, 14 West Nile-positive mosquito pools have been detected in five counties: Arenac, Kent, Lapeer, Oakland and Saginaw.

The West Nile virus season was less severe in 2019. There were 12 human cases and two deaths, the state said.

Most people infected with the virus will not develop symptoms of illness. However, some become sick three to 15 days after exposure. About one in five infected people will have mild illness with fever and about one in 150 infected people will become severely ill.

Mild illness symptoms include headache, body aches, joint pain, vomiting, diarrhea and a rash.

People 60 and older are more susceptible to severe symptoms, including encephalitis or meningitis.

The state said to stay protected, residents should apply insect repellents that contain the active ingredient DEET, wear light-colored, long-sleeved shirts and long pants when outdoors and empty water from mosquito breeding sites around the home.

For information, visit Michigan.gov/westnilevirus