An agent for use in a vaccine therapy to prevent or treat a Burkholderia infection in a mammal, wherein the agent is selected from a polypeptide of SEQUENCE ID NO: 1, or a therapeutically effective variant thereof having at least 90% sequence identity with SEQUENCE ID NO: 1; a polypeptide of SEQUENCE ID NO: 3, or a therapeutically effective variant thereof having at least 90% sequence identity with SEQUENCE ID NO: 3; and an immunogenic portion of the polypeptides of SEQUENCE ID NO: 1 or SEQUENCE ID NO: 3.