How does Vibrant address the potential for cross-reactivity between antibodies to different Borrelia species to determine which species is actually present in the patient sample?

Within Borrelia species there is variation in the protein produced at the amino acid level. So, if you layout the protein sequences next to each other you will find overlapping regions and unique regions. If an individual produces an antibody to a unique region of a particular species, only that particular species is going to show reactivity. Therefore, it is extremely important to test for all species. If the antibody is towards an overlapping region, then you see multiple species showing reactivity. The more species you test for, the more sensitive the results, and the lower the likelihood of a false positive.