Table 3.
Estimated vaccine effectiveness 28 days after vaccination in subpopulations according to baseline characteristics versus unvaccinated individuals
|
COVID-19-related hospital admission |
COVID-19-related hospital admission requiring critical or intensive care |
COVID-19-related death |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Vaccinated (events/person-years) | Unvaccinated (events/person-years) | Vaccine effectiveness (95% CI) | Vaccinated (events/person-years) | Unvaccinated (events/person-years) | Vaccine effectiveness (95% CI) | Vaccinated (events/person-years) | Unvaccinated (events/person-years) | Vaccine effectiveness (95% CI) | ||
| Sex | ||||||||||
| Male | ||||||||||
| Scheme A | 39/5452 | 165/5341 | 76% (68 to 84) | 8/5457 | 48/5351 | 82% (68 to 94) | 4/5458 | 32/5353 | 87% (71 to 98) | |
| Scheme B | 39/4660 | 84/4666 | 53% (34 to 69) | 11/4661 | 28/4672 | 60% (28 to 83) | 6/4662 | 20/4674 | 71% (38 to 93) | |
| Western Cape* | 4/700 | 6/700 | 32% (−36 to 73) | .. | .. | .. | .. | .. | .. | |
| Female | ||||||||||
| Scheme A | 113/14 676 | 280/14 432 | 60% (51 to 68) | 11/14 686 | 62/14 451 | 83% (70 to 93) | 7/14 688 | 44/14 454 | 84% (70 to 95) | |
| Scheme B | 110/18 982 | 369/19 013 | 70% (64 to 77) | 33/18 990 | 118/19 036 | 72% (60 to 82) | 11/18 995 | 68/19 046 | 83% (71 to 92) | |
| Western Cape* | 10/1954 | 34/1952 | 69% (47 to 87) | .. | .. | .. | .. | .. | .. | |
| Age | ||||||||||
| Age 18–49 years | ||||||||||
| Scheme A | 83/15 222 | 217/14 931 | 62% (52 to 71) | 8/15 231 | 44/14 946 | 81% (66 to 94) | 2/15 232 | 24/14 948 | 90% (73 to 100) | |
| Scheme B | 66/15 612 | 209/15 962 | 68% (59 to 76) | 14/15 616 | 55/15 976 | 73% (56 to 87) | 6/15 619 | 23/15 980 | 70% (40 to 94) | |
| Western Cape* | 7/1950 | 27/1948 | 71% (46 to 90) | .. | .. | .. | .. | .. | .. | |
| ≥50 years | ||||||||||
| Scheme A | 70/4906 | 228/4842 | 66% (57 to 76) | 11/4912 | 67/4856 | 83% (72 to 93) | 9/4913 | 52/4859 | 83% (68 to 93) | |
| Scheme B | 83/8030 | 244/7717 | 67% (59 to 75) | 30/8035 | 91/7732 | 68% (53 to 80) | 11/8038 | 65/7740 | 84% (72 to 93) | |
| Western Cape* | 5/703 | 13/702 | 52% (−14 to 81) | .. | .. | .. | .. | .. | .. | |
| Coexisting risk factors for severe COVID-19 | ||||||||||
| None | ||||||||||
| Scheme A | 61/13 682 | 180/13 395 | 66% (57 to 76) | 9/13 689 | 34/13 407 | 75% (54 to 91) | 5/13 689 | 18/13 409 | 72% (40 to 92) | |
| Scheme B | 59/15 283 | 206/15 328 | 71% (62 to 79) | 20/15 288 | 61/15 342 | 67% (49 to 82) | 5/15 290 | 32/15 346 | 84% (65 to 97) | |
| One or more | ||||||||||
| Scheme A | 91/6446 | 265/6378 | 66% (57 to 73) | 11/6455 | 77/6394 | 86% (76 to 94) | 6/6456 | 58/6398 | 89% (78 to 98) | |
| Scheme B | 90/8359 | 247/8351 | 63% (54 to 72) | 24/8363 | 85/8366 | 71% (57 to 83) | 12/8367 | 56/8374 | 78% (60 to 89) | |
| HIV status | ||||||||||
| HIV positive | ||||||||||
| Scheme A | 12/997 | 14/705 | .. | .. | .. | .. | .. | .. | .. | |
| Scheme B | 18/3802 | 66/3731 | 73% (58 to 85) | 4/3802 | 19/3736 | 79% (51 to 96) | 5/3803 | 15/3738 | 65% (13 to 93) | |
| No HIV or unknown | ||||||||||
| Scheme A | 140/19 131 | 431/19 068 | 68% (61 to 73) | 140/19 131 | 431/19 068 | 85% (76 to 92) | 10/19 147 | 72/19 101 | 86% (76 to 94) | |
| Scheme B | 131/19 840 | 387/19 948 | 66% (59 to 73) | 40/19 849 | 127/19 972 | 68% (56 to 79) | 12/19 854 | 73/19 982 | 83% (72 to 97) | |
| Hypertension status | ||||||||||
| Hypertension present | ||||||||||
| Scheme A | 41/2439 | 150/2416 | 73% (63 to 81) | 5/2443 | 45/2424 | 89% (76 to 98) | 6/2444 | 35/2426 | 84% (68 to 97) | |
| Scheme B | 56/4074 | 164/4115 | 66% (55 to 76) | 18/4077 | 62/4125 | 70% (52 to 85) | 9/4080 | 39/4130 | 76% (52 to 90) | |
| No hypertension | ||||||||||
| Scheme A | 111/17 689 | 294/17 357 | 63% (55 to 70) | 14/17 700 | 66/17 377 | 78% (64 to 89) | 6/17 701 | 40/17 380 | 86% (72 to 96) | |
| Scheme B | 93/19 568 | 289/19 564 | 68% (60 to 75) | 26/19 574 | 84/19 583 | 69% (55 to 82) | 8/19 577 | 49/19 590 | 83% (69 to 95) | |
| No previous documented COVID-19 | ||||||||||
| Scheme A | 147/17 957 | 433/17 645 | 67% (61 to 72) | 19/17 972 | 109/17 672 | 83% (73 to 90) | 10/17 974 | 67/17 678 | 86% (75 to 94) | |
| Scheme B | 142/21 030 | 440/21 026 | 68% (61 to 73) | 43/21 038 | 142/21 055 | 70% (59 to 80) | 16/21 044 | 86/21 066 | 81% (70 to 91) | |
| Western Cape* | 9/2046 | 36/2044 | 73% (52 to 90) | .. | .. | .. | .. | .. | .. | |
*
Data on admissions requiring critical or intensive care were not available and too few events occurred to enable analysis of COVID-19-related deaths; Western Cape data on coexisting clinical risk factors for severe COVID-19 not available.