An Alternative Serological Measure for Assessing Foot-and-Mouth Disease Vaccine Efficacy against Homologous and Heterologous Viral Challenges in Pigs

Figures

• 

  Figure 1. Observed protection rates based on levels of log10 virus neutralized test (VNT) titers following the challenge in the vaccine-challenge studies. (A) The protection rate is depicted by a relationship with the VNT titer at 21 dpv, and (B) the protection rate is described according to each VNT titer at 28 dpv. The vaccine and challenge strains in each study are indicated as hyphenated words at the top of each plot. Each bar represents a group of animals sharing the indicated titer ±0.15 (reciprocal log10). The numbers of animals with each titer level are indicated at the top of each bar. Gray part of bars, protected; black part of bars, not protected.

• 

  Figure 2. Estimated probability of protection for virus neutralization tests (VNT) against the challenge strains. (A) The plots of the probability of protection are depicted according to each VNT titer at 21 dpv, and (B) the plots of probability of protection are depicted according to each VNT titer at 28 dpv. Color indicates individual groups: three groups in 21-dpv models, group 21D-1 (blue), group 21D-2 (green), and group 21D-3 (gray); two groups in 28-dpv models, group 28D-1 (red), and group 28D-2 (purple).

• 

  Figure 3. Logistic models of the probability of protection following the challenge for the log10 VNT titer. The plot shows the posterior median for the probability of protection for group 21D-1, group 21D-2, and group 21D-3 in the 21-dpv model, and group 28D-1 and 28D-2 in the 28-dpv model.

• 

  Figure 4. The ROC curves for the diagnostic performance of the indirect FMD vaccine potency test based on the VNT logistic regression models. (A) The plots of the ROC curves are depicted for different groups in the 21 dpv model, and (B) the plots of the ROC curves are depicted for different groups in the 28 dpv model. The AUC (area under the curve) of each model is indicated with a 95% confidence interval over the x-axis of each plot.