1. Centro de Investigaciones Biológicas Margarita Salas (CIB-CSIC), Ramiro de Maeztu 9, 20840 Madrid, Spain.
2. Department of Animal Health, Istituto Zooprofilattico Sperimentale della Sardegna, 07100 Sassari, Italy.
3. Centro de Biología Molecular Severo Ochoa (CBMSO), Calle Nicolás Cabrera, 1, 28049 Madrid, Spain.
4. Dpt. Biotechnology, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Ctra. de la Coruña km 7.5, 28040 Madrid, Spain.
5. The Pirbright Institute, Ash Road, Pirbright, Woking, GU24 ONF, United Kingdom.
6. Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Immunology, Suedufer 10, 17493 Greifswald-Insel Riems, Germany.