Table 1.
ELISA for the detection of IgG targeting the native, B.1.351, B.1.617.2, and P.1 spike proteins using serum from variant-naïve, SARS-CoV-2-positive individuals at weeks 4 and 16 post-diagnosis.
| Native spike | B.1.351 spike | B.1.617.2 spike | P.1 spike | ||||||
|---|---|---|---|---|---|---|---|---|---|
| W4 | W16 | W4 | W16 | W4 | W16 | W4 | W16 | ||
| OD450 (A.U) | Pos | 2.0 ± 0.7 | 1.6 ± 0.6 | 1.4 ± 0.7 | 1.5 ± 0.8 | 1.4 ± 0.5 | 1.4 ± 0.5 | 1.0 ± 0.3 | 1.1 ± 0.5 |
| OD450 (A.U) | Neg | 0.18 ± 0.04 | 0.32 ± 0.11 | 0.16 ± 0.04 | 0.17 ± 0.05 | 0.02 ± 0.03 | 0.02 ± 0.03 | 0.02 ± 0.03 | 0.02 ± 0.03 |
| Threshold (A.U) | 0.4 | 0.6 | 0.25 | 0.2 | 0.1 | 0.1 | 0.1 | 0.1 | |
| COVID + sera | # Pos | 32 | 31 | 32 | 31 | 30 | 30 | 31 | 31 |
| # Neg | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 | |
| Control sera | # Pos | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
| # Neg | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | |
| AUC | 1.00 | 1.00 | 1.00 | 0.99 | 1.00 | 1.00 | 1.00 | 1.00 | |
| p value | < 0.0001 | < 0.0001 | < 0.0001 | < 0.01 | < 0.0001 | < 0.0001 | < 0.0001 | < 0.0001 | |
| Sensitivity | 100 | 100 | 100 | 96 | 100 | 100 | 100 | 100 | |
| Specificity | 100 | 100 | 100 | 88 | 100 | 100 | 100 | 100 | |