Validation of a diphtheria toxoid multiplex bead assay for serosurveys

We validated a multiplex bead assay for diphtheria toxoid IgG antibodies against the Vero cell toxin neutralization test using 1300 specimens (correlation = 0.88). At the >0.01 IU/mL cutoff for minimal seroprotection, sensitivity was 95% and specificity was 83%. Agreement for three categories (<0.01, 0.01 & minus;<0.1, >0.1 IU/mL) was 81% (kappa = 0.71). Published by Elsevier Inc.

Automated summary

The study validated a multiplex bead assay for diphtheria toxoid IgG antibodies against the Vero cell toxin neutralization test, showing a high correlation. Sensitivity was 95% and specificity was 83% at a cutoff of >0.01 IU/mL for minimal seroprotection, with a high agreement across three categories of IU/mL values.