Table 2.
Overview of antibody and neutralization results from suspect positive cattle: RBD-ELISA (standardized OD); surrogate neutralization assay (sVNT; percentage of inhibition); indirect immunofluorescence test (IFA). The cut-off OD value for a suspect positive result in RBD-ELISA is ≥0.431. The cut-off for inhibition in sVNT is >43%. The cut-off for the IFA was 8. The suspect positive RBD-ELISA results, positive sVNT results and the highest titers in the IFA are marked in bold.
| Sample ID | Sampling Date | RBD-ELISA | sVNT | IFA |
|---|---|---|---|---|
| #184 | March 2020 | 0.632 | −1.1 | <8 |
| #89 | March 2020 | 0.737 | −2.2 | <8 |
| #825 | April 2020 | 0.506 | 19.6 | 8 |
| #700 | April 2020 | 0.678 | 89.2 | 128 |
| #25 | June 2020 | 0.786 | 18.1 | <8 |
| #44 | June 2020 | 0.583 | 0.47 | <8 |
| #2 | June 2020 | 0.451 | 6.0 | <8 |
| #334 | July 2020 | 0.470 | 12.3 | <8 |
| #520 | October 2020 | 0.836 | 19.5 | <8 |
| #597 | June 2021 | 1.729 | 98.9 | 128 |
| #589 | June 2021 | 0.742 | 8.4 | <8 |
| #631 | November 2021 | 0.741 | 11.3 | <8 |
| #644 | December 2021 | 0.868 | 49.5 | 16 |
| #407 | April 2022 | 0.442 | 13.6 | <8 |
| #419 | April 2022 | 0.483 | 27.5 | <8 |