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International audience; We recently reported on a successful vaccine for carp against SVCV based on the intramuscular injection of aDNA plasmid encoding the SVCV glycoprotein (SVCV-G). This shows that the intramuscular (i.m.) route ofvaccination is suitable to trigger protective responses against SVCV, and that the SVCV G-protein is a suitablevaccine antigen. Yet, despite the general success of DNA vaccines, especially againstfish rhabdoviruses, theirpractical implementation still faces legislative as well as consumer's acceptance concerns. Furthermore, the i.m.route of plasmid administration is not easily combined with most of the current vaccination regimes largelybased on intraperitoneal or immersion vaccination. For this reason, in the current study we evaluated possiblealternatives to a DNA-based i.m. injectable vaccine using the SVCV-G protein as the vaccine antigen. To this end,we tested two parallel approaches: thefirst based on the optimization of an alginate encapsulation method fororal delivery of DNA and protein antigens; the second based on the baculovirus recombinant expression oftransmembrane SVCV-G protein in insect cells, administered as whole-cell subunit vaccine through the oral andinjection route. In addition, in the case of the oral DNA vaccine, we also investigated the potential benefits of themucosal adjuvantsEscherichia colilymphotoxin subunit B (LTB). Despite the use of various vaccine types, doses,regimes, and administration routes, no protection was observed, contrary to the full protection obtained with ourreference i.m. DNA vaccine. The limited protection observed under the various conditions used in this study, thenature of the host, of the pathogen, the type of vaccine and encapsulation method, will therefore be discussed indetails to provide an outlook for future vaccination strategies against SVCV