Table 2.
Descriptive characteristics of long term care residents tested for SARS-CoV-2 between 30 December 2021 and 27 April 2022 in Ontario, Canada, comparing those who received a third dose 84 or more days previously with those who received a third dose less than 84 days previously or a fourth dose. Values are numbers (percentages) unless stated otherwise
| Characteristics | Third dose ≥84 days before test (n=88 742) | Third dose <84 days before test (n=28 906) | Standardised difference* | Fourth dose <7 days before test (n=11 681) | Standardised difference* | Fourth dose ≥7 days before test (n=70 979) | Standardised difference* | ||
|---|---|---|---|---|---|---|---|---|---|
| Mean (SD) age (years) | 84.06 (9.47) | 82.97 (8.93) | 0.12 | 84.29 (9.42) | 0.02 | 83.57 (9.61) | 0.05 | ||
| Age group (years): | |||||||||
| 60-69 | 8184 (9.2) | 2721 (9.4) | 0.01 | 1030 (8.8) | 0.01 | 7215 (10.2) | 0.03 | ||
| 70-79 | 17 773 (20.0) | 6460 (22.3) | 0.06 | 2237 (19.2) | 0.02 | 14 793 (20.8) | 0.02 | ||
| ≥80 | 62 785 (70.8) | 19 725 (68.2) | 0.05 | 8414 (72.0) | 0.03 | 48 971 (69.0) | 0.04 | ||
| Men | 27 500 (31.0) | 10 646 (36.8) | 0.12 | 3528 (30.2) | 0.02 | 22 004 (31.0) | 0 | ||
| Public health unit region | |||||||||
| Central East | 7336 (8.3) | 2002 (6.9) | 0.05 | 886 (7.6) | 0.03 | 5236 (7.4) | 0.03 | ||
| Central West | 16 753 (18.9) | 4666 (16.1) | 0.07 | 1794 (15.4) | 0.09 | 11 174 (15.7) | 0.08 | ||
| Durham | 3152 (3.6) | 957 (3.3) | 0.01 | 479 (4.1) | 0.03 | 2991 (4.2) | 0.03 | ||
| Eastern | 7364 (8.3) | 2249 (7.8) | 0.02 | 1232 (10.5) | 0.08 | 8772 (12.4) | 0.13 | ||
| North | 7919 (8.9) | 2885 (10.0) | 0.04 | 1090 (9.3) | 0.01 | 7866 (11.1) | 0.07 | ||
| Ottawa | 4102 (4.6) | 1513 (5.2) | 0.03 | 742 (6.4) | 0.08 | 4590 (6.5) | 0.08 | ||
| Peel | 4742 (5.3) | 1795 (6.2) | 0.04 | 615 (5.3) | 0 | 3033 (4.3) | 0.05 | ||
| South West | 12 145 (13.7) | 3560 (12.3) | 0.04 | 1553 (13.3) | 0.01 | 11 031 (15.5) | 0.05 | ||
| Toronto | 18 661 (21.0) | 6726 (23.3) | 0.05 | 2595 (22.2) | 0.03 | 12 397 (17.5) | 0.09 | ||
| York | 6222 (7.0) | 2196 (7.6) | 0.02 | 685 (5.9) | 0.05 | 3720 (5.2) | 0.07 | ||
| Missing | 346 (0.4) | 357 (1.2) | 0.09 | 10 (0.1) | 0.06 | 169 (0.2) | 0.03 | ||
| Long term care facility in outbreak at time of test | 51 090 (57.6) | 16 079 (55.6) | 0.04 | 7037 (60.2) | 0.05 | 28 600 (40.3) | 0.35 | ||
| Past positive SARS-CoV-2 test result (>90 days) | 14 461 (16.3) | 3051 (10.6) | 0.17 | 1889 (16.2) | 0 | 10 343 (14.6) | 0.05 | ||
| Week of test† | |||||||||
| 30 Dec to 5 Jan | 22 328 (25.2) | 5062 (17.5) | 0.19 | 224 (1.9) | 0.72 | 0 (0.0) | 0.82 | ||
| 6 Jan to 12 Jan | 22 001 (24.8) | 5232 (18.1) | 0.16 | 1300 (11.1) | 0.36 | 272 (0.4) | 0.79 | ||
| 13 Jan to 19 Jan | 14 050 (15.8) | 4222 (14.6) | 0.03 | 3044 (26.1) | 0.25 | 1100 (1.5) | 0.52 | ||
| 20 Jan to 26 Jan | 9491 (10.7) | 3495 (12.1) | 0.04 | 2735 (23.4) | 0.34 | 3655 (5.1) | 0.21 | ||
| 27 Jan to 2 Feb | 5169 (5.8) | 2764 (9.6) | 0.14 | 2101 (18.0) | 0.38 | 5282 (7.4) | 0.07 | ||
| 3 Feb to 9 Feb | 2570 (2.9) | 1903 (6.6) | 0.17 | 904 (7.7) | 0.22 | 4723 (6.7) | 0.18 | ||
| 10 Feb to 16 Feb | 1237 (1.4) | 1188 (4.1) | 0.17 | 360 (3.1) | 0.11 | 3980 (5.6) | 0.23 | ||
| 17 Feb to 23 Feb | 912 (1.0) | 962 (3.3) | 0.16 | 136 (1.2) | 0.01 | 3658 (5.2) | 0.24 | ||
| 24 Feb to 2 Mar | 981 (1.1) | 964 (3.3) | 0.15 | 110 (0.9) | 0.02 | 3801 (5.4) | 0.24 | ||
| 3 Mar to 9 Mar | 766 (0.9) | 779 (2.7) | 0.14 | 86 (0.7) | 0.01 | 3452 (4.9) | 0.24 | ||
| 10 Mar to 16 Mar | 849 (1.0) | 575 (2.0) | 0.09 | 117 (1.0) | 0 | 3791 (5.3) | 0.25 | ||
| 17 Mar to 23 Mar | 892 (1.0) | 411 (1.4) | 0.04 | 98 (0.8) | 0.02 | 4073 (5.7) | 0.26 | ||
| 24 Mar to 30 Mar | 1109 (1.2) | 369 (1.3) | 0 | 106 (0.9) | 0.03 | 4805 (6.8) | 0.28 | ||
| 31 Mar to 6 Apr | 1454 (1.6) | 336 (1.2) | 0.04 | 99 (0.8) | 0.07 | 5929 (8.4) | 0.31 | ||
| 7 Apr to 13 Apr | 1567 (1.8) | 308 (1.1) | 0.06 | 99 (0.8) | 0.08 | 7525 (10.6) | 0.37 | ||
| 14 Apr to 20 Apr | 1680 (1.9) | 179 (0.6) | 0.11 | 75 (0.6) | 0.11 | 7342 (10.3) | 0.36 | ||
| 21 Apr to 27 Apr | 1686 (1.9) | 157 (0.5) | 0.12 | 87 (0.7) | 0.1 | 7591 (10.7) | 0.37 | ||
| Mean (SD) No of comorbidities | 4.06 ±1.55 | 4.29 ±1.56 | 0.15 | 4.05 ±1.53 | 0 | 4.04 ±1.56 | 0.01 | ||
| Type of comorbidity: | |||||||||
| Immunocompromised | 7775 (8.8) | 3543 (12.3) | 0.11 | 1031 (8.8) | 0 | 6212 (8.8) | 0 | ||
| Chronic respiratory disease |
31 568 (35.6) | 10 824 (37.4) | 0.04 | 4207 (36.0) | 0.01 | 26 096 (36.8) | 0.02 | ||
| Chronic heart disease | 32 212 (36.3) | 12 253 (42.4) | 0.12 | 4147 (35.5) | 0.02 | 25 737 (36.3) | 0 | ||
| Hypertension | 72 475 (81.7) | 24 249 (83.9) | 0.06 | 9563 (81.9) | 0.01 | 57 437 (80.9) | 0.02 | ||
| Diabetes | 34 821 (39.2) | 12 202 (42.2) | 0.06 | 4533 (38.8) | 0.01 | 27 890 (39.3) | 0 | ||
| Autoimmune disorders | 7249 (8.2) | 2216 (7.7) | 0.02 | 953 (8.2) | 0 | 5939 (8.4) | 0.01 | ||
| Chronic kidney disease‡ | 14 412 (16.2) | 6687 (23.1) | 0.17 | 1794 (15.4) | 0.02 | 11 595 (16.3) | 0 | ||
| Advanced liver disease | 2129 (2.4) | 861 (3.0) | 0.04 | 264 (2.3) | 0.01 | 1868 (2.6) | 0.01 | ||
| Dementia | 71 725 (80.8) | 20 109 (69.6) | 0.26 | 9546 (81.7) | 0.02 | 56 073 (79.0) | 0.05 | ||
| History of stroke or transient ischaemic attack |
15 623 (17.6) | 4950 (17.1) | 0.01 | 2016 (17.3) | 0.01 | 12 680 (17.9) | 0.01 | ||
| Frailty | 70 002 (78.9) | 26 149 (90.5) | 0.33 | 9310 (79.7) | 0.02 | 54 938 (77.4) | 0.04 |
SD=standard deviation.
*
Values >0.10 are considered clinically relevant. Comparing residents who received their third dose <84 days before their index test, fourth dose <7 days previously, and fourth dose ≥7 days previously with residents who received their third dose ≥84 days before their index test.
†
30 December, 31 December in 2021, and remaining dates in 2022.
‡
Chronic kidney disease in past five years or dialysis for three consecutive months.