1. Department of Clinical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA;
2. The Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA;
3. The Intracellular Pathogens Research Laboratory, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA;
4. The Department of Pathology, School of Medicine, University of California, Irvine, CA, USA