Table 2. Comparison of the sensitivity of SARS-CoV-2 antibody detection assays.
| ADAPT (n = 166 samples) | LIFE | |||||
|---|---|---|---|---|---|---|
| All samples (n = 645) | First and last samples (n = 302*) | |||||
| Positive samples, n (%) | Sensitivity % (95% CI) | Positive samples, n (%) | Sensitivity% (95% CI) | Positive samples, n (%) | Sensitivity% (95% CI) | |
| Spike IgG | ||||||
| Flow cytometry assay | 162 (98) | 98 (94–99) |
645 | n/a | 302 | n/a |
| EUROIMMUN | 121 (73) | 73 (65–80) |
n/a | n/a | n/a | n/a |
| Spike IgM | ||||||
| Flow cytometry assay | 127 (77) | 76** (70–83) |
608 (94) | 94**, ^^ (92–96) |
276 (91) | 91**, ^^ (87–94) |
| S1/S2 Spike IgG | ||||||
| DiaSorin LIAISON SARS-CoV-2 S1/S2 IgG assay | 134 (81) | 81 (74–86) |
n/a | n/a | n/a | n/a |
| Nucleocapsid IgG | ||||||
| Abbott Architect SARS-CoV-2 assay | 116 (70) | 70 (62–77) |
472 (73) | 73 (70–77) |
222 (74) | 74 (68–78) |
| EUROIMMUN | 121 (73) | 73 (65–80) |
n/a | n/a | n/a | n/a |
| Nucleocapsid/Spike IgG*** | n/a | n/a | 577 (89) | 89 (87–92) |
271 (90) | 90 (86–93) |
| Membrane IgG | ||||||
| Flow cytometry assay | 87 (52) | 52 (45–60) |
n/a | n/a | 173 (57) | 57 (51–63) |
| Envelope IgG | 4 (2) | 2 (0.8–6) | 0 | 0 | 0 | 0 |
*Only first and last samples of LIFE cohort were tested for Membrane IgG.
**Sensitivity is influenced by IgM seroreversion in 5 ADAPT and 14 LIFE donors.
***Positivity determined using a 2-step clinical diagnostic testing with the Abbott Architect SARS-CoV-2 Nucleocapsid IgG assay, followed by the EUROIMMUN Spike IgG assay.
^^ Please refer to the materials and methods for time of collection as it affects the IgM serostatus
SARS-CoV-2, Severe Acute Respiratory Syndrome Coronavirus 2.