The Michigan Department of Agriculture and Rural Development is aware of 15 horses that have been tested for equine herpes virus type-1 as a precautionary measure. Only horses displaying fever or mild signs of illness were tested. One additional horse from the index farm tested positive for EHV-1 and is under veterinary care; and the other 14 tested negative. This brings Michigan’s 2015 positive EHV-1 cases to a total of two.
The positive horse is at a facility already under quarantine because of exposure to the March 19 EHV-1-positive horse.
MDARD still has four facilities under quarantine for monitoring of horses exposed to the March 19 EHV-1-positive horse.
As a reminder, the March 19 positive EHV-1 horse traveled for competitions/shows in Barry County on February 28 and March 7 and traveled for training to a facility in Livingston County on March 9, 11 and 14. If your horse was at one of these locations on any of these dates, MDARD asks that you isolate your horse and monitor its temperature twice a day. Any horse with a fever over 101.5 or showing any signs suggestive of EHV, especially respiratory or neurologic signs should contact MDARD and their own veterinarian.
When determining if your horse may have been exposed to the Michigan EHV positive horse, pay attention to the county and date of events. For example, there was a show at Mississippi State University March 7, however, MSU is in Ingham County and the MSU March 7 event is not considered a potential exposure event. When monitoring your horse, temperatures should be taken for 28 days beyond the day of potential exposure to EHV.
Michigan State University College of Veterinary Medicine — March 24, 2015
An 8-year-old American Quarter Horse gelding, used for barrel racing, presented to Michigan State University Veterinary Medical Center March 18 for acute onset of neurologic disease.
The gelding tested positive for equine herpes virus type-1 (EHV-1) and was placed in isolation. The gelding was euthanized March 21 due to deterioration of clinical signs in the face of aggressive supportive care.
No other EHV-1 cases have been reported in Michigan at this time. All equine in-patients at MSU were tested March 21 for EHV-1. At that time all horses tested negative.
