Cell culture-derived vaccine for rabbit haemorrhagic disease virus 2.

The ongoing circulation of pathogenic rabbit haemorrhagic disease viruses (RHDV1 and RHDV2) worldwide makes vaccination of domestic rabbits essential. Most commercially available RHDV vaccines are prepared by inactivating virus purified from the tissues of infected rabbits. Although highly effective, the production of such vaccines requires the use of rabbits in both manufacturing and quality assurance, raising ethical concerns. Inactivated cell culture-derived vaccines for RHDVs have not been described, as RHDV could not be grown reliably in vitro since its discovery. A recently developed rabbit liver-derived cell culture system supports RHDV replication to high titres, providing opportunities to explore development of a cell culture-based vaccine. Here, we compared a commercially available vaccine with an experimental RHDV2 vaccine derived from culture-grown virus. All rabbits, vaccinated with either formulation, survived RHDV2 challenge. These preliminary results demonstrate the potential of the RHDV culture system as an alternative platform for RHDV vaccine production.