Serology and Diagnostics
The interpretation of an antibody test result can be complex because antibody testing is used for many reasons. Depending on the antibodies tested for, antibody testing can be used for (1) diagnosis of infection, (2) identification of previous exposure to pathogens (particularly in unvaccinated animals), and (3) assessment of immunity prior to or following vaccination ( Table 7 ). Clinicians should understand when and why to perform antibody testing and use this knowledge to make evidence-based decisions prior to vaccination.