Table 1.
Demographics, characteristics and humoral response rates of the study population, and comparison between healthcare workers with and without a COVID-19 booster dose in vaccine breakthrough infection.
| Variable | Total (n = 435) | VBI (n= 101) | Not VBI (n = 334) | p-Value |
|---|---|---|---|---|
| Demographic characteristics | ||||
| Age, years * | 34.0 (28–42.5) | 33 (27–38) | 34 (29–43) | 0.084 a |
| Sex (%) | 0.027 b | |||
| Female | 340 (78.16) | 87 (86.14) | 253 (75.75) | |
| Male | 95 (21.84) | 14 (13.86) | 81 (24.25) | |
| Laboral area (%) | 0.044 | |||
| Phlebotomy | 57 (13.10) | 14 (13.86) | 43 (12.87) | |
| Customer service | 144 (33.10) | 27 (26.73) | 117 (35.03) | |
| Maintenance service | 65 (14.95) | 12 (11.89) | 53 (15.87) | |
| Analytic process | 122 (28.05) | 40 (39.60) | 82 (24.55) | |
| Administrative | 47 (10.80) | 8 (7.92) | 39 (11.68) | |
| Infection before the third wave (%) | 138 (31.72) | 27 (26.73) | 111 (33.23) | 0.219 b |
| Before the first dose of BBIBP-CorV | 122 (28.04) | 26 (25.74) | 96 (28.74) | 0.556 b |
| After the first dose of BBIBP-CorV | 11 (2.52) | 0 (0.00) | 11 (3.30) | 0.075 c |
| After the second dose of BBIBP-CorV | 14 (3.21) | 6 (5.94) | 8 (2.40) | 0.077 c |
| Number of doses | 0.633 b | |||
| Two doses of BBIBP-CorV | 138 (31.72) | 34 (33.66) | 104 (31.14) | |
| Two doses of BBIBP-CorV plus booster BNT162b2 | 297 (68.28) | 67 (66.34) | 230 (68.86) | |
| Time from the first infection until the third wave | 507.5 (317–558) | 541 (344–599) | 492 (317–557) | 0.084 a |
| Days since first infection until VBI | - | 539.5 (310–579) | - | |
| Days since infection before the first dose of BBIBP-CorV until VBI | - | 555 (366–610) | - | |
| Days since infection after the second dose of BBIBP-CorV until VBI | - | 175.5 (135–208) | - | |
| Humoral response rates21 days after the second dose (%) | ||||
| Elecys Anti-SARS-CoV-2 S (n = 303; VBI = 74, not VBI = 229) (+) | ||||
| ≥0.8 | 296 (97.69) | 73 (98.64) | 223 (97.38) | 0.999 c |
| ≥500 | 120 (39.60) | 27 (36.48) | 93 (40.61) | 0.528 b |
| ≥1000 | 84 (27.72) | 17 (22.97) | 67 (29.25) | 0.379 c |
| Ab neutralization cPass (n = 280; VBI = 69, not VBI = 211) (+) | ||||
| ≥30% | 265 (94.64) | 66 (95.65) | 199 (94.31) | 0.999 c |
| ≥60% | 230 (82.14) | 51 (73.91) | 179 (84.83) | 0.047 c |
| ≥90% | 125 (44.64) | 25 (36.23) | 100 (47.39) | 0.125 c |
| 90 days after the second dose (%) | ||||
| Elecys Anti-SARS-CoV-2 S (n = 384; VBI = 91, not VBI = 293) (+) | ||||
| ≥0.8 | 372 (96.88) | 86 (94.50) | 286 (97.61) | 0.165 c |
| ≥500 | 128 (33.33) | 26 (28.57) | 102 (34.81) | 0.270 b |
| ≥1000 | 76 (19.79) | 15 (16.48) | 61 (20.81) | 0.452 c |
| Ab neutralization cPass (n = 356; VBI = 83, not VBI = 273) (+) | ||||
| ≥30% | 311 (87.36) | 71 (85.54) | 240 (87.91) | 0.574 c |
| ≥60% | 217 (60.96) | 48 (57.83) | 169 (61.90) | 0.523 c |
| ≥90% | 122 (34.27) | 22 (24.17) | 100 (36.63) | 0.089 b |
| 180 days after the second dose (%) | ||||
| Elecys Anti-SARS-CoV-2 S (n = 395; VBI = 92, not VBI = 303) (+) | ||||
| ≥0.8 | 384 (97.22) | 88 (95.65) | 296 (97.68) | 0.290 c |
| ≥500 | 132 (33.42) | 20 (21.73) | 112 (36.96) | 0.008 c |
| ≥1000 | 75 (18.99) | 11 (11.95) | 64 (21.12) | 0.050 c |
| Ab neutralization cPass (n = 383; VBI = 88, not VBI = 295) (+) | ||||
| ≥30% | 261 (68.15) | 54 (61.36) | 207 (70.16) | 0.120 b |
| ≥60% | 185 (48.30) | 30 (34.09) | 155 (52.54) | 0.002 b |
| ≥90% | 112 (29.24) | 17 (19.31) | 95 (32.20) | 0.020 b |
| 210 days after second dose (%) | ||||
| Elecys Anti-SARS-CoV-2 S (n = 366; VBI = 91; not VBI = 275) (+) | ||||
| ≥0.8 | 365 (99.73) | 90 (98.90) | 275 (100.0) | 0.249 c |
| ≥500 | 323 (88.25) | 78 (85.71) | 245 (89.09) | 0.452 c |
| ≥1000 | 307 (83.88) | 75 (82.41) | 232 (84.36) | 0.742 c |
| Ab neutralization cPass (n = 364; VBI = 90, not VBI = 274) (+) | ||||
| ≥30% | 345 (94.78) | 84 (93.33) | 261 (95.25) | 0.584 c |
| ≥60% | 329 (90.38) | 80 (88.88) | 249 (90.87) | 0.544 c |
| ≥90% | 307 (84.34) | 76 (84.44) | 231 (84.30) | 0.999 c |
a: U Mann-Withney; b: Chi2; c: Fisher exact; * Median (interquartile range); (+) positive; VBI: vaccine breakthrough infection.