Table 1.
Neutralizing Antibody and Anti-S/RBD Antibody Titers of 267 Noninfected COVID-19 Participants Following Vaccination
| Characteristic | Neutralizing Antibody, %, Mean (95% CI) | S/RBD Antibody, U/mL, Mean (95% CI) | ||||
|---|---|---|---|---|---|---|
| 2 wk | 16 wk | 24 wk | 2 wk | 16 wk | 24 wk | |
| All, n = 267 | 95.4 (94.7–96.1) | 85.5 (84.1–86.8) | 72.6 (70.6–74.7) | 2545 (2333–2757) | 1190 (1114–1266) | 919 (858–980) |
| Sex | ||||||
| Male, n = 25 | 94.5 (91.5–97.5) | 83.2 (78.4–88.0) | 70.6 (63.6–77.6) | 2275 (1612–2937) | 985 (767–1203) | 808 (628–987) |
| ↕NS | ↕NS | ↕NS | ↕NS | ↕NS | ↕NS | |
| Female, n = 242 | 95.5 (94.8–96.2) | 85.7 (84.1–86.8) | 72.8 (70.7–75.0) | 2573 (2349–2797) | 1212 (1131–1292) | 930 (865–995) |
| Age group 1, y | ||||||
| 20–39, n = 156 | 96.1 (95.9–96.3) | 87.4 (85.9–88.8) | 75.4 (72.9–78.0) | 2789 (2494–3083) | 1301 (1199–1402) | 1013 (930–1096) |
| ↕ ∗ | ↕ ∗∗ | ↕ ∗∗ | ↕ ∗∗ | ↕ ∗∗ | ↕ ∗∗∗ | |
| 40–59, n = 111 | 94.4 (92.8–96.0) | 82.8 (80.4–85.2) | 68.8 (65.5–72.1) | 2202 (1913–2492) | 1037 (928–1145) | 791 (705–876) |
| Age group 2, y | ||||||
| 20–29, n = 61 | 96.3 (96.1–96.5) | 88.7 (86.5–91.0) | 75.9 (71.6–80.2) | 2815 (2398–3231) | 1363 (1184–1541) | 1058 (910–1206) |
| ↕NS | ↕NS | ↕NS | ↕NS | ↕NS | ↕NS | |
| 30–39, n = 95 | 96.0 (95.7–96.3) | 86.5 (84.6–88.4) | 75.1 (71.9–78.4) | 2772 (2364–3181) | 1260 (1137–1384) | 984 (885–1083) |
| ↕NS | ↕NS | ↕ ∗ | ↕NS | ↕NS | ↕NS | |
| 40–49, n = 77 | 94.7 (93.2–96.1) | 82.8 (80.2–85.4) | 68.0 (64.0–72.0) | 2455 (2074–2835) | 1055 (915–1194) | 799 (687–912) |
| ↕NS | ↕NS | ↕NS | ↕NS | ↕NS | ↕NS | |
| 50–59, n = 34 | 93.7 (89.5–97.9) | 82.8 (77.6–88.0) | 70.7 (64.5–76.9) | 1631 (1294–1967) | 997 (826–1167) | 771 (649–893) |
Student t test was used to compare mean values. ∗P < .05, ∗∗P < .01, ∗∗∗P < .001.
Abbreviations: NS, not significantly different; RBD, receptor binding domain; S, spike protein.