EHV-1 Update

May 28th, 2011

In a news release dated May 27, 2011,  the Texas Animal Health Commission confirmed a case of the neurological form of equine herpes virus (EHV-1) in a Quarter racehorse stabled in Ector County, Texas. Preliminary investigation indicated no connection to the NCHA Western National Championships in Ogden Utah, April 29 to May 8, 2011, site of a recent outbreak.

All horses on the Ector County premises are under quarantine and will be managed according to USDA recommendations for confirmed cases.

As of May 26, 2011, according to USDA, APHIS, Veterinary Services, a total of 75 confirmed EHV-1 or EHM cases have been reported in nine states: Arizona, California, Colorado, Idaho, New Mexico, Nevada, Oregon, Utah and Washington. Of the 75 confirmed cases, 58 are horses that were at the NCHA event in Ogden, Utah.

The USDA further confirms that 11 horses have died from the virus or have been euthanized because of it – nine of which were exposed at the Ogden event and two which had secondary or tertiary contact with horses that had been exposed at Ogden. Of the 75 confirmed cases, the largest number (31) are from Colorado.

The Texas Animal Health Commission references the USDA report in its own May 27, 2011 news release, but also reports: “Regarding the Ogden, UT event, there are currently 12 known horses in Texas that attended the event and 174 cohorts (stablemates) remaining under movement restrictions.

According to the USDA report, Table 2., Status of Primary Exposed Horses, 26 horses from Texas were exposed at Ogden.