1. Department of Infectious Diseases, St Jude Children's Research Hospital, Memphis, TN 38105, USA
2. University Cooperativa de Colombia School of Veterinary Medicine, Villavicencio 500001, Colombia
3. Department of Pathobiological Sciences, University of Wisconsin-Madison School of Veterinary Medicine, Madison, WI 53706, USA
4. GIRGA Group, University de los Llanos School of Veterinary Medicine, Villavicencio 500001, Colombia