Table 1.
Demographic data and characteristics of the main study cohort at the 12-month collection round
| Total (N = 1325)a | Infection-naive (N = 955)b | Infected before Omicron (N = 207)c | Infected with Omicron (N = 163)d | P-value | |
|---|---|---|---|---|---|
| Sex | |||||
| Female | 1145 (86.4%) | 833 (87.2%) | 180 (87.0%) | 132 (81.0%) | 0.0961e |
| Male | 180 (13.6%) | 122 (12.8%) | 27 (13.0%) | 31 (19.0%) | |
| Age (years) | |||||
| Median (IQR) | 52 (41–59) | 54 (43–61) | 47 (36–57) | 46 (39–55) | <0.0001e |
| <40 | 316 (23.8%) | 193 (20.2%) | 70 (33.8%) | 53 (32.5%) | <0.0001f |
| >40–60 | 718 (54.2%) | 518 (54.2%) | 107 (51.7%) | 93 (57.1%) | |
| >60 | 291 (22.0%) | 244 (25.5%) | 30 (14.5%) | 17 (10.4%) | |
| BMI | |||||
| Median (IQR) | 24 (22–27)g | 24 (22–27)h | 24 (22–27)i | 24 (22–26)j | 0.3646e |
| Underweight | 17 (1.4%) | 10 (1.2%) | 6 (3.1%) | 1 (0.8%) | 0.0626f |
| Normal | 681 (57.9%) | 480 (56.3%) | 115 (60.2%) | 86 (64.7%) | |
| Overweight | 305 (25.9%) | 227 (26.6%) | 43 (22.5%) | 35 (26.3%) | |
| Obese | 174 (14.8%) | 136 (15.9%) | 27 (14.1%) | 11 (8.3%) | |
| Infection status | |||||
| Infected before Omicron | 129 (9.7%) | N.A. | 129 (62.3%) | N.A. | N.A. |
| Ancestral variantk | 54 (20.2%) | N.A. | 54 (41.9%) | N.A. | |
| Alpha variant | 19 (7.1%) | N.A. | 19 (14.7%) | N.A. | |
| Delta variant | 56 (21.0%) | N.A. | 56 (43.4%) | N.A. | |
| Infected before Omicron and reinfected | 78 (5.9%) | N.A. | 78 (37.7%) | N.A. | |
| Ancestral variantk | 46 (28.5%) | N.A. | 46 (59.0%) | N.A. | |
| Alpha variant | 19 (11.8%) | N.A. | 19 (24.4%) | N.A. | |
| Delta variant | 13 (8.1%) | N.A. | 13 (16.7%) | N.A. | |
| Infected with Omicron | 163 (12.3%) | N.A. | N.A. | 163 (100%) | |
| Infection-naive | 492 (37.1%) | 492 (51.5%) | N.A. | N.A. | |
| Infection-naive but will be infected with Omicron | 463 (34.9%) | 463 (48.5%) | N.A. | N.A. | |
| Time between first and second dose (days) | |||||
| Median (IQR) | 30 (29–33) | 30 (29–33) | 30 (29–33) | 30 (29–33) | 0.7171e |
| Time between first and third dose (days) | |||||
| Median (IQR) | 295 (287–302) | 294 (287–302) | 298 (291–309) | 294 (285–302) | <0.0001e |
IQR Interquartile range, N.A. Not Applicable.
aParticipants who contributed with a sample for the cellular immunity studies: 874 individuals.
bParticipants who contributed with a sample for the cellular immunity studies: 651 individuals.
cParticipants who contributed with a sample for the cellular immunity studies: 124 individuals.
dParticipants who contributed with a sample for the cellular immunity studies: 99 individuals.
eKruskal–Wallis test (two-sided) between participants infected before Omicron, participants infected with Omicron and infection-naive participants.
fChi-squared test (two-sided) between participants infected before Omicron, participants infected with Omicron and infection-naive participants.
gMissing values: 148 individuals.
hMissing values: 102 individuals.
iMissing values: 16 individuals.
jMissing values: 30 individuals.
kAncestral variant dominance in Denmark comprised a wide combination of the clades 20E (EU1), 20A (EU2), 20A/S:439K, 20B/S:626S, among others70.