1. Faculty of Veterinary Medicine, Usmanu Danfodiyo University, PMB 2346, Sokoto, Nigeria
2. Laboratory of Vaccines and Immunotherapeutics, Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
3. Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400, Selangor, Malaysia
4. Faculty of Veterinary Medicine, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
5. Division of Virology, Central Veterinary Institute, Wageningen University, P.O. Box 65, NL8200 Lelystad, Netherlands