Attenuation and Immunogenicity of a Live High Pathogenic PRRSV Vaccine Candidate with a 32-Amino Acid Deletion in the nsp2 Protein

Figure 3

Mean anti-PRRSV antibody levels measured by ELISA. Samples were considered positive for antibody to PRRSV if the sample-to-positive (S/P) ratio was equal to or greater than 0.4. The geometric mean data with standard deviations (error bars) were shown.