1. Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, 4467 TAMU, College Station, Texas 77843-4467, USA
2. Texas Animal Health Commission, 2105 Kramer Lane, Austin, Texas 78758, USA
3. Department of Veterinary Integrative Biosciences, College of Veterinary Medicine, Texas A&M University, 4458 TAMU, College Station, Texas 77843-4458, USA
4. Texas Department of State Health Services, Zoonosis Control, 401 East Franklin, Suite 210, El Paso, Texas 79901, USA