Seroprevalence by demographic characteristics
| Characteristic | No. of samples tested | No. of positives | Seropositive, % (95% CI)* |
|---|---|---|---|
| Overall | 916 | 212 | 22.9 (20.1–26.1) |
| Sex | |||
| Female | 451 | 96 | 21.0 (17.3–25.4) |
| Male | 462 | 115 | 24.9 (20.9–28.8) |
| Self-described | 3 | 1 | – |
| Age group, yr | |||
| 18–24 | 95 | 22 | 22.6 (14.8–32.8) |
| 25–34 | 233 | 49 | 20.9 (15.8–27.1) |
| 35–44 | 247 | 54 | 21.5 (16.5–27.6) |
| 45–54 | 157 | 36 | 23.2 (16.8–31.0) |
| 55–64 | 94 | 28 | 29.6 (20.6–40.5) |
| ≥ 65 | 80 | 22 | 28.1 (18.5–40.1) |
| Vaccinated† | |||
| No | 458 | 107 | 23.0 (19.1–27.4) |
| Yes, 1 dose | 393 | 93 | 23.7 (19.5–28.6) |
| Yes, 2 doses | 65 | 12 | 18.8 (10.7–30.9) |
| History of previous SARS-CoV-2 infection | |||
| Yes | 88 | 69 | 78.1 (67.5–85.9) |
| No | 600 | 81 | 13.5 (10.9–16.7) |
| Unknown | 11 | 2 | 18.3 (4.3–52.8) |
| Median household income based on FSA, $ | |||
| 40 000–59 999 | 9 | 1 | 10.6 (1.3–52.4) |
| 60 000–79 999 | 97 | 22 | 22.1 (14.4–32.4) |
| 80 000–99 999 | 570 | 130 | 22.7 (19.1–26.6) |
| ≥ 100 000 | 228 | 56 | 24.6 (19.0–31.3) |
| Essential worker | |||
| Yes | 228 | 50 | 22.1 (16.8–28.4) |
| No | 352 | 73 | 20.6 (16.3–25.5) |
| Prefer not to answer | 113 | 21 | 18.3 (11.8–27.2) |
| Completed education | |||
| High school or less | 121 | 31 | 25.4 (17.9–34.7) |
| College, trade, certificate | 89 | 18 | 20.1 (12.6–30.5) |
| University degree | 453 | 89 | 19.6 (16.0–23.9) |
| Prefer not to answer | 30 | 6 | 19.4 (8.4–38.8) |
| Multigenerational household | |||
| Yes | 125 | 30 | 23.1 (16.0–32.1) |
| No | 451 | 88 | 19.7 (16.0–24.0) |
| Prefer not to answer | 78 | 15 | 18.7 (11.1–29.8) |
| Location | |||
| Region of Peel | 830 | 194 | 23.2 (20.2–26.5) |
| City of Brampton | 742 | 178 | 23.8 (20.6–27.3) |
| City of Caledon | 39 | 7 | 18.4 (8.6–34.9) |
| City of Mississauga | 49 | 9 | 18.4 (9.4–32.9) |
| FSA income by household size categories | |||
| Lowest income | 80 | 23 | 28.0 (18.5–39.9) |
| Category 2 | 121 | 22 | 18.0 (11.8–26.6) |
| Category 3 | 152 | 34 | 22.4 (16.0–30.5) |
| Category 4 | 117 | 21 | 18.1 (11.7–26.9) |
| Highest income | 102 | 17 | 16.8 (10.4–26.1) |
Note: CI = confidence interval, FSA = forward sortation area.
↵* Seropositivity estimates and 95% CI estimates from mixed models accounting for multiple responders per household. For overall model, the intraclass correlation coefficient = 0.17.
↵† Test interpretation for vaccinated individuals differed from that for nonvaccinated individuals; see the Methods section.