Disclosed and claimed are compositions containing a Borrelia burgdorferi antigen, and methods for making and using them. The antigen can be OspA. The compositions can contain at least one additional antigen from a pathogen other than Borrelia burgdorferi. The compositions are useful for eliciting an immunological response in a host mammal susceptible to Lyme Disease and to the mammalian pathogen other than Borrelia burgdorferi. Suitable host mammals include dogs, pups, horses, and, the additional antigen can be of a canine, equine or feline pathogen, such as rabies, canine distemper, adenovirus, coronavirus, parainfluenza and parvovirus. No significant efficacy interference is observed.