Efficacy and safety of simultaneous vaccination with two modified live virus vaccines against porcine reproductive and respiratory syndrome virus types 1 and 2 in pigs

• DOI: 10.1016/j.vaccine.2017.11.059
• Publication Date: 2017-11-28T00:47:20Z
• Authors: Charlotte S. Kris...; L.K. Kvisgaard; M. Pawlowski; S. Holmgaard Carlsen; C.K. Hjulsager; P.M.H. Heegaard; A. Bøtner; T. Stadejek; S. Haugegaard; L.E. Larsen
• Keywords: Viremia

The objective of the study was to compare responses pigs vaccinated with a PRRS MLV vaccine against PRRSV-1 or PRRSV-2 simultaneously both vaccines. Furthermore, efficacy two PRRSV vaccination strategies assessed following challenge. experimental design included four groups 4-weeks old SPF-pigs. On day 0 (DPV0), 1–3 (N = 18 per group) were modified live virus vaccines (MLV) containing (VAC-T1), (VAC-T2) (VAC-T1T2). One group left unvaccinated 12). DPV 62, from 1–4 mingled in new and challenged (DPC 0) PRRSV-1, subtype 1, 2 PRRSV-2. DPC 13/14 all necropsied. Samples collected after detected majority positive until 28, but few still viremic 62 days vaccination. Virus nasal swabs 7–14. No overt clinical signs observed resulted clear reduction viral load serum challenge, whereas there limited effect on challenge strains. Vaccination had less impact viremia protective effects simultaneous Type 1 single comparable. None decreased lungs at necropsy. In conclusion, elicited comparable commercial protected only partially heterologous Thus, administration is an option herds types.