Table 1.
Various antibody-based COVID-19 tests, their features, and available validation data.
| Methodology Used for the Test | Main Findings | Number of Subjects | Categorization of Subjects | Sensitivity (%) | Specificity (%) | Positive Predictive Value | Negative Predictive Value | Reference |
|---|---|---|---|---|---|---|---|---|
| Lateral flow immunoassay (LFIA) | The IgM–IgG combined assay showed better sensitivity than a single IgM or IgG test. | 525 | 397 were PCR positive and remaining 128 were negative |
88.66 | 90.63 | NA | NA | [114] |
| Chemiluminescence assay | Showed higher efficiency for the detection of IgM and IgG anti-SARS CoV-2 antibodies | 125 | 61 were PCR positive patients and 64 were negative |
73.3 (IgM) 76.7 (IgG) | 92.2 100 |
81.5 NA |
88.1 90.1 |
[122] |
| Chemiluminescence assay | IgG showed higher titre value than that of IgM | 76 | 43 were PCR positive and the remaining 33 were probable cases |
48.1 IgM 88.9 IgG | 100 IgM 90.9 IgG | NA | NA | [123] |
| Chemiluminescence assay | Automated CLIA analyzer | 176 | 125 PCR confirmed cases | 95–95.5 | 100 | 100 | NA | [124] |
| Chemiluminescence assay | Positive results after two weeks of symptom onset | 34 | All the subjects were PCR confirmed patients |
94.1 | NA | NA | NA | [89] |
| Chemiluminescence assay | Highest seroconversion was observed around 20–22 days after symptom onset | 285 | All the 285 were PCR positive patients |
94 (IgM) 100 (IgG) | NA | NA | NA | [125] |
| Chemiluminescence assay | Rapid | 476 | 276 PCR positive patients, and 200 negative volunteers |
57.2 (IgM) 71.4 (IgG) | NA | NA | NA | [126] |
| ELISA | IgM and IgG were reliably positive after one month of symptom onset | 24 | All were PCR positive patients |
74 | 100 | NA | NA | [127] |
| ELISA | All patients tested positive for IgG and some patients tested negative for IgM | 60 | Samples collected from convalescent patients | 78 IgM 100 IgG |
NA | NA | NA | [128] |
| ELISA | The IgM reached 100% about one month of symptom onset | 173 | All the subjects were PCR positive patients |
100 (>15 days) | NA | NA | NA | [112] |
| ELISA | IgA, IgM, and IgG were detected from 5 days from the onset of symptoms | 140 | 82 PCR positive and 58 suspected cases |
75.6 (IgM in confirmed cases) 93.1 (IgM in probable cases) |
NA | NA | NA | [120] |
| ELISA | IgG and IgA ELISAs in along with EUROLabworkstation (Euroimmu) | 39 PCR positive cases, 13 were IgG and IgA positive and 11 IgA only positive | NA | 91.9% (IgG)73.0% (IgA) | NA | NA | [129] | |
| IgM /IgG immunoassay | The rapid test | 110 | 30 were PCR positive cases, 50 were persons with respiratory symptoms and 30 were PCR negatives |
18.4 | 91.7 | 87.5 | 26.2 | [130] |
| Immunochromatography | The IgM-positive rate showed an elevation from 11.1% in early-stage to 74.2% in late-stage disease. The positive rate of IgG in patients was 3.6% in early-stage and 96.8% in late-stage disease | 105 | 105 patients | 68.6 | NA | NA | NA | [131] |
| Modified cytopathogenic assay | Patients with severe clinical manifestations showed higher antibody titre | 70 | The study comprises inpatients and Convalescent patients |
100 | NA | NA | NA | [132] |
| Immunofluorescence assay | Rapid and easy to use | 59 | 59 suspected patients; 24 PCR positive cases |
87.5 | NA | NA | NA | [133] |
| Rapid immunoassay | The accuracy was 40% in the first week and 93.9% after 2 | 179 | Patients included PCR positive (n = 90) and PCR negative (n = 89) |
85.6 | 91 | 95.1 | 82.7 | [134] |
| Rapid lateral flow assay | Fast, point of care test | 67 | 67 were PCR positive patients |
11 (<7 days) 92 (7–14 days) 96 (>14 days) |
NA | NA | NA | [135] |
| Single Molecular Array (SIMOA) | Indicates disease severity | 81 | All were SARS-CoV-2 confirmed patients |
86 | 100 | NA | NA | [136] |