Table 2.
Demographic characteristics of cases and controls in samples used to estimate effectiveness of the mRNA-1273 vaccine against symptomatic SARS-CoV-2 BA.1 Omicron infection, symptomatic BA.2 Omicron infection, and any symptomatic Omicron infection.
| Characteristics | Effectiveness against symptomatic SARS-CoV-2 BA.1 Omicron infection | Effectiveness against symptomatic SARS-CoV-2 BA.2 Omicron infection | Effectiveness against any symptomatic SARS-CoV-2 Omicron infection | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Casesa (PCR-positive) | Controlsa (PCR-negative) | SMDb | Casesc (PCR-positive) | Controlsc (PCR-negative) | SMDb | Casesd (PCR-positive) | Controlsd (PCR-negative) | SMDb | |
| N = 3574 | N = 6176 | N = 13,537 | N = 13,537 | N = 21,810 | N = 13,288 | ||||
| Median age (IQR)—years | 30 (15–38) | 29 (11–38) | 0.07e | 28 (10–37) | 28 (10–38) | 0.01e | 28 (9–37) | 28 (9–38) | 0.00e |
| Age group—no. (%) | |||||||||
| <10 years | 670 (18.8) | 1282 (20.8) | 0.07 | 3149 (23.3) | 3149 (23.3) | 0.00 | 5576 (25.6) | 3496 (26.3) | 0.03 |
| 10–19 years | 300 (8.4) | 549 (8.9) | 1475 (10.9) | 1475 (10.9) | 1692 (7.8) | 993 (7.5) | |||
| 20–29 years | 771 (21.6) | 1286 (20.8) | 2633 (19.5) | 2633 (19.5) | 4311 (19.8) | 2608 (19.6) | |||
| 30–39 years | 1037 (29.0) | 1788 (29.0) | 3427 (25.3) | 3427 (25.3) | 5692 (26.1) | 3368 (25.4) | |||
| 40–49 years | 475 (13.3) | 797 (12.9) | 1512 (11.2) | 1512 (11.2) | 2575 (11.8) | 1568 (11.8) | |||
| 50–59 years | 231 (6.5) | 349 (5.7) | 880 (6.5) | 880 (6.5) | 1346 (6.2) | 853 (6.4) | |||
| 60–69 years | 68 (1.9) | 89 (1.4) | 315 (2.3) | 315 (2.3) | 400 (1.8) | 261 (2.0) | |||
| 70+ years | 22 (0.6) | 36 (0.6) | 146 (1.1) | 146 (1.1) | 218 (1.0) | 141 (1.1) | |||
| Sex | |||||||||
| Male | 1769 (49.5) | 3232 (52.3) | 0.06 | 7717 (57.0) | 7717 (57.0) | 0.00 | 12,678 (58.1) | 7745 (58.3) | 0.00 |
| Female | 1805 (50.5) | 2944 (47.7) | 5820 (43.0) | 5820 (43.0) | 9132 (41.9) | 5543 (41.7) | |||
| Nationalityf | |||||||||
| Bangladeshi | 74 (2.1) | 132 (2.1) | 0.07 | 443 (3.3) | 443 (3.3) | 0.00 | 762 (3.5) | 547 (4.1) | 0.06 |
| Egyptian | 224 (6.3) | 393 (6.4) | 897 (6.6) | 897 (6.6) | 1249 (5.7) | 715 (5.4) | |||
| Filipino | 524 (14.7) | 890 (14.4) | 1402 (10.4) | 1402 (10.4) | 2396 (11.0) | 1389 (10.5) | |||
| Indian | 535 (15.0) | 1007 (16.3) | 2256 (16.7) | 2256 (16.7) | 3719 (17.1) | 2306 (17.4) | |||
| Nepalese | 74 (2.1) | 132 (2.1) | 431 (3.2) | 431 (3.2) | 625 (2.9) | 363 (2.7) | |||
| Pakistani | 118 (3.3) | 221 (3.6) | 658 (4.9) | 658 (4.9) | 1042 (4.8) | 633 (4.8) | |||
| Qatari | 866 (24.2) | 1554 (25.2) | 3,364 (24.9) | 3364 (24.9) | 5117 (23.5) | 2955 (22.2) | |||
| Sri Lankan | 42 (1.2) | 74 (1.2) | 262 (1.9) | 262 (1.9) | 444 (2.0) | 271 (2.0) | |||
| Sudanese | 212 (5.9) | 385 (6.2) | 789 (5.8) | 789 (5.8) | 1273 (5.8) | 758 (5.7) | |||
| Other nationalities | 905 (25.3) | 1388 (22.5) | 3,035 (22.4) | 3035 (22.4) | 5183 (23.8) | 3351 (25.2) | |||
The table was generated by combining the matched samples of the various time-since-vaccination strata.
IQR interquartile range, PCR polymerase chain reaction, SMD standardized mean difference.
aCases and controls were matched one-to-two by sex, 10-year-age group, nationality, and calendar week of PCR test.
bSMD is the difference in the mean of a covariate between groups divided by the pooled standard deviation. An SMD < 0.1 indicates adequate matching.
cCases and controls were matched one-to-one by sex, 10-year-age group, nationality, and calendar week of PCR test.
dCases and controls were matched two-to-one by sex, 10-year-age group, nationality, and calendar week of PCR test.
eSMD is for the mean difference between groups divided by the pooled standard deviation.
fNationalities were chosen to represent the most populous groups in Qatar.