Increased risk for eastern equine encephalitis for horses in 2019

Increased spring 2019 rainfall may result in an increased risk for certain equine diseases.

July 11, 2019 - Author: ,

EEE graphic
Photo by MDARD

The Michigan Department of Agriculture & Rural Development (MDARD) is warning horse owners that due to excessive rainfall this spring and summer, there are heightened concerns about eastern equine encephalitis (EEE) activity this year. Additionally, disease trends have shown that in Michigan, equine outbreaks of EEE can occur every nine to 10 years. The last outbreak in 2010 involved 56 confirmed cases.

It’s not too late to vaccinate. MDARD urges horse owners to work with their veterinarian to safeguard their horses from EEE and West Nile virus (WNV).

Both diseases are commonly seen from summer to late fall and are spread by mosquitoes. Mosquitoes carrying WNV have already been detected in Michigan and while mosquitoes are not typically tested for EEE, cases are seen each year, especially in southwestern Michigan and the Upper Peninsula. Both diseases cause neurologic issues, and EEE is particularly concerning, as horses with the disease have a low chance of survival. The most commonly reported signs of EEE and WNV are incoordination, inability to rise, lethargy, seizures or tremors.

In addition to vaccination, horse owners should protect their horses against mosquitoes by applying repellent, eliminating standing water and bringing horses indoors from early evening until after sunrise when mosquitoes are most prevalent.

Eastern equine encephalitis and WNV are reportable diseases to MDARD. If you suspect your horse has EEE or WNV, contact your veterinarian.

For more information on EEE and WNV, visit Equine Disease Communication Center's Disease Information.

Tags: 4-h animal science, 4-h horses & ponies, agriculture, eastern equine encephalitis, horse diseases, horses, msu extension, west nile virus


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