Eastern Equine Encephalitis, West Nile Virus cases detected in horses for first time this year

LANSING, Mich. (FOX 2) - The state has confirmed its first cases of Eastern equine encephalitis and West Nile virus in a domestic animal after positive tests came back in horses living in Mecosta County and Calhoun County. 

Both horses were unvaccinated for the respective diseases, with EEE reported in a 7-year-old Standardbred gelding in Mecosta and West Nile confirmed in a 4-month-old Belgian colt. 

While these aren't the first cases to be reported in Michigan, they are reminders of how each illness spreads - as well as current circulation among mosquito populations.

"These detections indicate these diseases are present and circulating within the state’s mosquito population, so protecting animals from being exposed to these insects is crucial. Preventing mosquito bites will prevent mosquito-borne diseases," said state veterinarian Dr. Nora Wineland. 

Both diseases bring a potentially severe round of side effects with a tiny percentage of those who test positive developing neurologic symptoms. 

MORE: State confirms first case of EEE

They pass through mosquitoes and cannot be transmitted from horses to other horses or people. Transmission usually occurs in late summer and early fall. 

So far, EEE cases have been detected in four mosquito pools in Bay, Barry, and Saginaw counties. The WNV cases were in 98 different mosquito pools in Bay, Genesee, Iosco, Kalamazoo, Kent, Oakland, Saginaw, Tuscola, Washtenaw, and Wayne counties. 

"These discoveries are a reminder that the EEE virus is here in Michigan and provides warning that people can also become infected by a mosquito," said Dr. Natasha Bagdasarian, MDHHS chief medical executive. "Michigan residents are urged to take precautions and protect themselves from mosquito bites as EEE is one of the most dangerous mosquito-borne diseases in the U.S., with a 33 percent fatality rate among people who become ill."

The state is typically on alert for the diseases until the first freeze, which kills most of the mosquitoes. 

Learn more for about the diseases on the state health department here.