December 1, 2009

Four of eight US states affected by an outbreak of the equine venereal disease, contagious equine metritis, are now considered free of the disease.

Dr John Clifford, in his latest report to the World Organisation for Animal Health (OIE), said Georgia, Indiana, Iowa, and Kentucky were now clear.

Dr Clifford, deputy administrator with the Animal and Plant Health Inspection Service, which is part of the US Department of Agriculture, said a comprehensive investigation continues to be conducted by state and federal agriculture authorities into the outbreak, discovered late last year.

As of the November 17 - his latest report - horses that had tested positive for the bacteria, Taylorella equigenitalis, and all potentially exposed horses that had been located, either remained under under quarantine or hold order until determined as negative.

A total of 233 stallions, 211 exposed and all 22 of the formerly positive stallions, have now completed their entire testing and treatment, he said, and are now negative for the disease.

Another 19 exposed stallions have had at least one set of negative cultures, he said.

A total of 676 mares - 671 exposed to the disease and all five that proved postitive - have completed their testing and treatment protocol and are now negative.

"Overall, 909 (91.7 per cent) of the 991 horses involved have completed their entire testing and treatment protocol, and have been determined to be negative," Dr Clifford said.