Table 2.
Characteristics of subjects included in analysis of association of vaccination with SARS-CoV-2 infection in adults, during delta-predominant period (Oct 1–Dec 31, 2021).
| Variable | Total (N = 27,301) | SARS-CoV-2 status |
||
|---|---|---|---|---|
| Negative (controls) | Positive (cases) | p-value | ||
| Number (%) | 25,171 (92.2) | 2130 (7.8) | - | |
| Age, years | ||||
| Median (IQR) | 37 (28, 49) | 37 (28, 49) | 37 (26, 50) | 0.36 |
| Age group, n (%) | ||||
| 18–29 | 8202 (30.0) | 7491 (29.7) | 711 (33.4) | <0.01 |
| 30–39 | 7147 (26.2) | 6667 (26.5) | 480 (22.5) | |
| 40–49 | 5334 (19.5) | 4948 (19.7) | 386 (18.1) | |
| 50–59 | 3707 (13.6) | 3465 (13.8) | 242 (11.4) | |
| 60–69 | 2097 (7.7) | 1905 (7.6) | 192 (9.0) | |
| ≥70 | 814 (2.9) | 695 (2.7) | 119 (5.6) | |
| Gender, n (%) | ||||
| Male | 12,745 (46.7) | 11,693 (46.5) | 1052 (49.4) | <0.01 |
| Female | 14,556 (53.3) | 13,478 (53.6) | 1078 (50.6) | |
| Vaccination status, n (%) | ||||
| Unvaccinated | 9697 (35.5) | 8570 (34.0) | 1127 (52.9) | <0.01 |
| Vaccinated one dose only | 3360 (12.3) | 3001 (11.9) | 359 (16.9) | |
| Vaccinated two doses only | 13,045 (47.8) | 12,406 (49.3) | 639 (30.0) | |
| Vaccinated three doses | 1199 (4.4) | 1194 (4.7) | 5 (0.2) | |
| Type of primary vaccine series (n = 13,045), n (%) | ||||
| SV/SP-AZ | 6609 (50.7) | 6333 (51.1) | 276 (43.2) | NA |
| SV-SV or SP-SP | 4770 (36.6) | 4485 (36.1) | 285 (44.6) | |
| AZ-AZ | 1326 (10.2) | 1251 (10.1) | 75 (11.7) | |
| PFZ-PFZ | 194 (1.5) | 191 (1.5) | 3 (0.5) | |
| AZ-PFZ/Mod | 133 (1.0) | 133 (1.1) | 0 | |
| SV/SP-PFZ/Mod | 11 (0.1) | 11 (0.1) | 0 | |
| Mod–Mod | 2 (0.02) | 2 (0.02) | 0 | |
| Type of third vaccine dose (n = 1197),an (%) | ||||
| PFZ | 210 (17.6) | 210 (17.6) | 0 | 0.40 |
| AZ | 879 (73.4) | 874 (73.3) | 5 (100) | |
| Mod | 108 (9.0) | 108 (9.1) | 0 | |
| Median (IQR) time since last vaccination,bdays | 53 (28, 84) | 53 (28, 84) | 48 (29, 79) | 0.22 |
| Median (IQR) time since last vaccination (two doses only)c | 53 (32, 79) | 53 (32, 79) | 49 (30, 74) | 0.35 |
| Vaccination coverage | ||||
| Completed primary vaccine series, n (%) | 14,244 (52.2) | 13,600 (54.0) | 644 (30.2) | <0.01 |
| Completed third vaccine dose, n (%) | 1199 (4.4) | 1194 (4.7) | 5 (0.2) | <0.01 |
SV = CoronaVac (Sinovac), SP = Sinopharm, AZ = ChAdOx1 nCoV-19 (AstraZeneca), PFZ = BNT162b2 (Pfizer-BioNTech), Mod = mRNA-1273 (Moderna).
a
Vaccine type missing in 2 (0.02%).
b
Date of last vaccination missing in 258 (1.5%).
c
Date of last vaccination missing in 96 (0.7%).