SARS-CoV-2 antibody tests of human milk in included studies
| Author | n=X | Method used | SARS-CoV-2 IgG (unspecified) | Anti-SARS-CoV-2 nucleocapsid IgG | Anti-SARS-CoV-2 S2 IgG | Anti-SARS-CoV-2 IgA (unspecified) | Anti-SARS-CoV-2 nucleocapsid IgA | SARS-CoV-2 IgM (unspecified) | Anti- SARS-CoV-2 spike protein IgM | Total antibody reactivity against the RBD of the SARS-CoV-2 spike protein | SARS-CoV-2 neutralisation ability | Interval between onset of symptoms and presence of antibody | Duration antibody persisted from onset of COVID-19 until end of study |
| Dong et al 15 | 1 | ELISA. Specificity: S-protein. | Yes | NA | NA | Yes | NA | NA | NA | NA | NA | 26 days | 42 days |
| Yu et al 27 | 1 | Not stated | Yes | NA | NA | NA | NA | Yes | NA | NA | NA | 30 days | 30 days |
| Luo et al 21 | 1 | ELISA. Specificity: not stated. | No | NA | NA | No | NA | 100%, 4/4 individuals | NA | NA | NA | 7 days | Not known |
| Walczak et al 26 | 1 | Microsphere immunoassay. Specificity: not stated. | Yes | NA | NA | No | NA | Yes | NA | NA | NA | 10 days | 25 days |
| Lebrão et al 20 | 1 | ELISA Specificity: Not stated | No | NA | NA | Yes | Yes | NA | NA | NA | NA | 3 days | 6 days |
| van Keulen et al 25 | 29 | ELISA and bridging ELISA. Specificity: S-protein, RBD and N protein. | Yes | Yes | Yes | 83%; 24 individuals | 83%; 24 individuals | NA | NA | 83%; 24 individuals | 28%; 8 individuals | Mean 5.9 (SD 2.6) weeks | Not known |
| Gao et al 19 | 14 | Chemiluminescence immunoassay. Specificity: not stated. | Yes | NA | NA | NA | NA | 14%, 2 individuals | NA | NA | NA | 17–22 days | 28 days |
| Preßler et al 24 | 14 | Not stated. Specificity: nucleocapsid. | 14%; 2 individuals | NA | NA | 14%; 2 individuals | NA | NA | NA | NA | NA | 14 days | Not known |
| Fenizia et al 17 | 31 | Chemiluminescence immunoassay. Specificity: nucleocapsid and S-protein. | Yes | NA | NA | NA | NA | 10%, 1/10 individuals | NA | NA | NA | Not known | Not known |
| Peng et al 23 | 24 | ELISA. Specificity: not stated. | Negative | NA | NA | NA | NA | 42.1%, 8/19 individuals | NA | NA | NA | 3–79 days | 1–70 days |
| Favara et al 16 | 1 | Not stated. Specificity: N-antigen, S-antigen and RBD-antigen. | Yes | Yes | Yes | Yes | Yes | NA | NA | Yes | Yes | 28 days | 195 days |
| Fox et al 18 | 15 | ELISA. Specificity: trimeric S-protein, RBD of S-protein | NA | NA | NA | Yes | NA | 33.3%, 5 individuals | 33.3%, 5 individuals | 80%; 12 individuals | NA | Not known | Not known |
| Pace et al 22 | 18 | ELISA. Specificity: Spike (S2 and RBD) and nucleocapsid. | Yes | Yes | Yes | Yes | Yes | NA | NA | Yes | 62%;11 individuals | 0–22 days (3 asymptomatic) | Not known |
| Demers-Mathieu et al 28 | 7 | ELISA. Specificity: Spike (S1 or S2) | 100%; 7 individuals | NA | 100%; 7 individuals | 100%; 7 individuals | NA | 100%; 7 individuals | 100%; 7 individuals | NA | NA | Mean 47 (SD 24) days | Not known |
| Number of individuals who tested positive for antibodies/individuals who were tested for antibodies (%) | 106/144 (73.6%) | 48/48 (100%) | 55/55 (100%) | 69/86 (80%) | 44/49 (89.8%) | 29/71 (40.8%) | 12/22 (54.5%) | 55/63 (87.3%) | 20/48 (41.6%) | ||||
NA, not tested; RBD, receptor binding domain; S-protein, spike protein.