The present invention relates to vaccine compositions comprising a nucleic acid encoded by an equine arterivirus virus (EAV) open reading frame (ORF) 2 nucleic acid, and a nucleic vector comprising said EAV ORF 2. The invention further relates to the methods and kits encompassing the use of EAV ORF 2 containing vaccine compositions and nucleic acid vectors for the prevention and/or treatment of EAV infections.