The ISU Serology Section is offering the PRRSV Oral Fluid ELISA at an updated cutoff for surveillance testing. The updated cutoff is now 1.5 from the previous 1.0.
The following chart provides sensitivity and specificity data based adjusted cutoffs:
ELISA cut-off |
Diagnostic Sensitivity |
Diagnostic Specificity |
| S/P ≥ 0.4 | 100 | 95.2 |
| S/P ≥ 0.6 | 99.7 | 97.6 |
| S/P ≥ 0.8 | 98.4 | 98.6 |
| S/P ≥ 1.0 | 96.5 | 99.2 |
| S/P ≥ 1.2 | 94.6 | 99.4 |
| S/P ≥ 1.4 | 93.0 | 99.5 |
For more information please utilize “Adapting a porcine reproductive and respiratory syndrome virus (PRRSV) oral fluid antibody ELISA to routine surveillance” by Henao-Diaz et al.