Table 1.
Characteristics of the study cohort of FONASA affiliates, Feb 2 to Nov 10, 2021
| All participants | Laboratory-confirmed COVID-19 | Unvaccinated | Vaccination status: one dose | Vaccination status: two doses | Vaccination status: three doses | ||
|---|---|---|---|---|---|---|---|
| Overall population | 11 174 257 (100·0%) | 534 314 (4·8%) | 1 071 988 (9·6%) | 678 341 (6·1%) | 4 754 538 (42·6%) | 4 669 390 (41·8%) | |
| Sex | |||||||
| Female | 5 993 736 (54·0%) | 292 040 (4·9%) | 505 607 (8·4%) | 298 962 (5·0%) | 2 432 234 (40·6%) | 2 756 933 (46·0%) | |
| Male | 5 180 521 (46·0%) | 242 274 (4·7%) | 566 381 (10·9%) | 379 379 (7·3%) | 2 322 304 (44·8%) | 1 912 457 (36·9%) | |
| Age group, years | |||||||
| 16–19 | 736 905 (6·6%) | 32 034 (4·3%) | 62 457 (8·5%) | 127 731 (17·3%) | 514 370 (69·8%) | 32 347 (4·4%) | |
| 20–29 | 2 121 616 (19·0%) | 127 418 (6·0%) | 241 502 (11·4%) | 238 566 (11·2%) | 1 318 987 (62·2%) | 322 561 (15·2%) | |
| 30–39 | 2 001 611 (18·0%) | 116 321 (5·8%) | 243 211 (12·2%) | 144 776 (7·2%) | 1 059 332 (52·9%) | 554 292 (27·7%) | |
| 40–49 | 1 735 067 (16·0%) | 88 973 (5·1%) | 165 463 (9·5%) | 84 411 (4·9%) | 769 601 (44·4%) | 715 592 (41·2%) | |
| 50–59 | 1 795 580 (16·0%) | 79 308 (4·4%) | 136 770 (7·6%) | 51 346 (2·9%) | 548 956 (30·6%) | 1 058 508 (59·0%) | |
| 60–69 | 1 421 931 (13·0%) | 49 711 (3·5%) | 97 548 (6·9%) | 15 666 (1·1%) | 289 219 (20·3%) | 1 019 498 (71·7%) | |
| 70–79 | 881 220 (7·9%) | 26 116 (3·0%) | 65 071 (7·4%) | 8657 (1·0%) | 148 063 (16·8%) | 659 429 (74·8%) | |
| ≥80 | 480 327 (4·3%) | 14 433 (3·0%) | 59 966 (7·2%) | 7188 (1·5%) | 106 010 (22·1%) | 307 163 (64·0%) | |
| Comorbidities* | |||||||
| None | 7 586 853 (68·0%) | 361 575 (4·8%) | 832 456 (11·0%) | 558 203 (7·4%) | 3 611 727 (47·6%) | 2 584 467 (34·1%) | |
| ≥1 | 3 587 404 (32·0%) | 172 739 (4·8%) | 239 532 (6·7%) | 120 138 (3·4%) | 1 142 811 (31·9%) | 2 084 923 (58·1%) | |
| Nationality | |||||||
| Chilean | 10 427 613 (93·3%) | 501 394 (4·8%) | 895 370 (8·6%) | 616 986 (5·9%) | 4 417 917 (42·4%) | 4 497 340 (43·1%) | |
| Non-Chilean | 746 644 (6·7%) | 32 920 (4·4%) | 176 618 (23·7%) | 61 355 (8·2%) | 336 621 (45·1%) | 172 050 (23·0%) | |
As well as the listed characteristics, the main analysis model (table 2) also included individual-level income (seven groups) and location (16 regions; appendix pp 8–9). Using the χ2 test, we found statistically significant differences (p<0·001) both in the incidence of COVID-19 and according to vaccination status by sex, age group, comorbidities, nationality, region of residence, and income. More detailed cohort data are provided in the appendix (pp 8–10). The COVID-19 vaccines include AZD1222, Ad5-nCov, BNT162b2, and CoronaVac.
Coexisting conditions included chronic kidney disease, diabetes, cardiovascular disease (ie, hypertension, myocardial infarction), stroke, chronic obstructive pulmonary disease, haematological disease (ie, lymphoma, leukaemia, myeloma), autoimmune disease (ie, rheumatoid arthritis, juvenile idiopathic arthritis, systemic lupus erythematosus), HIV, and Alzheimer's disease and other dementias.