By KEVIN WALKER
Michigan Correspondent

LANSING, Mich. — Last week, the Michigan Department of Agriculture (MDA) announced two confirmed cases of Eastern equine encephalitis (EEE) in Michigan horses and several more cases not yet confirmed.

EEE is a mosquito-borne virus that can infect horses and humans, but not other types of livestock. The disease is often fatal. Birds can sometimes carry the virus without becoming extremely ill.

Mosquitoes feed off birds, get the virus and can then transmit the disease directly to their hosts. Horses, however, cannot transmit the disease to humans since there isn’t enough of it in their systems.

Michigan State University’s Diagnostic Center for Population and Animal Health confirmed that a three-month-old Percheron filly from Calhoun County and a 12-month old Arabian male from Barry County tested positive for the disease. The MDA has also been told several more horses in Cass County are believed to be positive for EEE, although it isn’t confirmed.

About two weeks ago, July 20, another horse from Cass County was tested by the National Veterinary Services Laboratories and found to have EEE. Signs of EEE infection in horses include staggering, depression and fever.

“It’s a serious inflammation of the brain that can result in death,” said Steven Halstead, Michigan’s state veterinarian. “For horses the fatality rate is 90 percent. For humans, it’s lower.”

Halstead said the one lucky thing about EEE is it can’t infect cattle, sheep, pigs or goats. Every once in a while he’s heard of a cat or dog becoming infected with it, but it’s rare.

“We’ve been dealing with EEE in Michigan since the early 1900s,” he said. “In the 1980s the state decided to do some aerial spraying in the Kalamazoo area.

“It’s been something that’s existed in Michigan. Mosquitoes are the main vector for EEE. They are sort of like flying syringes.”

The MDA and Department of Community Health offer the following tips to prevent becoming infected with the virus:

•Use insect repellant containing DEET, Picaridin, or oil of lemon eucalyptus; use more repellent if the mosquitoes continue to bite

•Fix holes in screens to keep the mosquitoes out and don’t leave windows open without a screen

•Since mosquitoes can lay eggs in standing water, get rid of it, such as in old tires or unused flower pots; do this on a weekly basis

Protect horses against EEE by getting them vaccinated each year with an approved vaccine. According to state officials, it’s not too late to have horses vaccinated this year.

Also, use approved insect repellents on horses. If possible, put horses in stables, stalls or barns during the hours of greatest mosquito activity – for example, from dusk to dawn.

According to the Centers for Disease Control, human cases of EEE are rare and most occur on the East and Gulf coasts. For more information on the human health effects of EEE, visit www.cdc.gov/EasternEquineEncephalitis /index.html

More information about EEE in horses is available by calling the MDA at 517-373-1077.