RESEARCH Open Access Immunization with a recombinant subunit OspA on average, 95.3 % (range 93.29- 98.08). The Risk Ratio for becoming infected with Borrelia burgdorferi antibodies in any

Full list of author information is available at the end of the articlegiven year if vaccine non-compliant was 21.41 (range 14.9 – 52.1). There was a high statistically significant relationship (p = <0.0001) in the observed data in terms of vaccination protocol compliance and the probability of Borrelia burgdorferi infection in each of the five years under study. Conclusions: The recombinant outer surface protein A (rOspA) vaccine for dogs is highly effective in preventing new seropositive cases of Borrelia burgdoferi infection over a five-year period in dogs living in an endemic area. Dogs that were vaccine protocol-compliant were significantly less likely to become infected (as indirectly assessed by antibody) with the agent of canine Lyme borreliosis as measured by Preventive Fraction and Risk Ratio calculations