Table 1 Unvaccinated donor’s characteristics in low and high NT titer groups
Low NT titer (< 1:160) | High NT titer (≥ 1:160) | p-value | |
|---|---|---|---|
Demographic parameters | |||
Gender - female | 263 (34.3%) (N = 766) | 84 (27.9%) (N = 301) | 0.050 |
Age (years) | 42.4 ± 0.4 (N = 766) | 47.4 ± 0.6 (N = 301) | < 0.001 |
Body weight (kg) | 85.2 ± 0.7 (N = 637) | 90.3 ± 1.1 (N = 199) | < 0.001 |
Height (cm) | 175.8 ± 0.3 (N = 634) | 176.0 ± 0.6 (N = 196) | 0.759 |
Body mass index (kg/m2) | 27.4 ± 0.2 (N = 633) | 29.1 ± 0.3 (N = 196) | < 0.001 |
Blood groups and total IgG | |||
Blood group 0 | 252 (32.9%) (N = 766) | 106 (35.2%) (N = 301) | 0.472 |
Blood group A | 314 (41.0%) (N = 766) | 127 (42.2%) (N = 301) | 0.730 |
Blood group B | 134 (17.5%) (N = 766) | 48 (15.9%) (N = 301) | 0.588 |
Blood group AB | 66 (8.6%) (N = 766) | 20 (6.6%) (N = 301) | 0.319 |
Rh(D) factor | 569 (81.8%) (N = 696) | 204 (80.0%) (N = 255) | 0.574 |
Total IgG (AU/ml) | 10.4 [9.1–11.9] (N = 732) | 10.6 [9.4–11.9] (N = 280) | 0.143 |
Serological testing | |||
Wantai semi-quantitative SARS-CoV-2 Ab test (index S/C)* | 17.9 [11.2–19.3] (N = 233) | 19.6 [18.6–20.5] (N = 52) | < 0.001 |
Abbott semi-quantitative SARS-CoV-2 Ab test (index S/C)* | 4.32 [2.62-6.0] (N = 455) | 6.94 [5.62–7.88] (N = 114) | < 0.001 |
Abbott quantitative SARS-CoV-2 Ab test (BAU/ml) | 187 [141–282] (N = 385) | 498 [310–1019] (N = 224) | < 0.001 |
Neutralization test (titer) | 31.2 [30.3–32.1] (N = 766) | 300.0 [288.2-312.4] (N = 301) | < 0.001 |
Timeline | |||
Days after start of COVID-19 symptoms | 53.0 [41.0-79.2] (N = 712) | 52.5 [40.0-79.8] (N = 254) | 0.822 |
0–60 days after start of COVID-19 symptoms | 418 (59.2%) (N = 706) | 150 (61.2%) (N = 245) | 0.597 |
60–120 days after start of COVID-19 symptoms | 221 (31.3%) (N = 706) | 76 (31.0%) (N = 245) | 1.000 |
120–180 days after start of COVID-19 symptoms | 67 (9.5%) (N = 706) | 19 (7.8%) (N = 245) | 0.518 |
Symptoms | |||
Hospitalization | 4 (1.0%) (N = 335) | 1 (1.0%) (N = 122) | 1.000 |
Fever | 191 (58.0%) (N = 329) | 88 (71.0%) (N = 124) | 0.013 |
Maximum body temperature (°C) | 38.0 [37.5–38.5] (N = 461) | 38.5 [37.8–39.0] (N = 189) | 0.001 |
Number of days with fever | 2.0 [1.0–4.0] (N = 559) | 4.0 [2.0–8.0] (N = 218) | < 0.001 |
Cough | 106 (32.0%) (N = 329) | 60 (48.0%) (N = 124) | 0.002 |
Anosmia | 209 (63.0%) (N = 330) | 58 (47.0%) (N = 124) | 0.002 |
Myalgia | 146 (44.0%) (N = 330) | 60 (48.0%) (N = 124) | 0.460 |
Dyspnea | 34 (10.0%) (N = 329) | 25 (20.0%) (N = 123) | 0.007 |
Fatigue | 168 (51.0%) (N = 329) | 63 (51.0%) (N = 124) | 1.000 |
Headache | 108 (33.0%) (N = 327) | 36 (29.0%) (N = 123) | 0.497 |