TABLE 3.
Correlation of WNV r-EIII indirect IgG ELISA testing of a panel of equine sera with results of HI/PRNT testing for anti-WNV antibody
| IgG indirect WNV r-EIII ELISA resulta | No. HI/PRNT positive | No. HI/PRNT negative |
|---|---|---|
| Positive | 31 | 0 |
| Equivocal | 8b | 2 |
| Negative | 2 | 14 |
a
Classifications for ELISA results with horse sera were based on results of testing with monkey sera (see Table 1) and assigned as follows: positive, corrected absorbance (minus absorbance in BSA control) ≥ 0.2; equivocal, absorbance of 0.1 to 0.2; negative, absorbance of <0.1.
b
For the ELISA equivocal samples, 6 of the 8 HI/PRNT positive samples were subsequently shown to be strongly IgM positive by independent IgM/IgG ELISA testing (see Results).