Table 1. Characteristics of surveillance population Canada, 2017/18 and 2018/19 (n = 91,549a).
| Characteristics of participants | 2017/18 | 2018/19 | Total 2017 and 2018 | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Controls | Vaccinees | Controls | Vaccinees | Controls | Vaccinees | |||||||||||||
| N | %b | 95% CI | N | %b | 95% CI | N | %b | 95% CI | N | %b | 95% CI | N | %b | 95% CI | N | %b | 95% CI | |
| Participants enrolled | ||||||||||||||||||
| Total | 28,938 | NA | NA | 44,373 | NA | NA | 43,734 | NA | NA | 38,397 | NA | NA | 72,672 | NA | NA | 82,770 | NA | NA |
| Participants who completed online safety survey | ||||||||||||||||||
| Total | 13,578 | 46.9c | NA | 30,173 | 68.0c | NA | 21,999 | 50.3c | NA | 25,799 | 67.2c | NA | 35,577 | 49.0c | NA | 55,972 | 67.6c | NA |
| Female | 8,345 | 61.5 | NA | 18,390 | 60.9 | NA | 13,418 | 61.0 | NA | 15,843 | 61.4 | NA | 21,763 | 61.2 | NA | 34,233 | 61.2 | NA |
| Number of vaccines in past 2 years | ND | NA | NA | 1,352 | 4.5 | NA | ND | NA | NA | 967 | 3.7 | NA | ND | NA | NA | 2,319 | 4.1 | NA |
| Age group completing survey | ||||||||||||||||||
| 6 months–4 years | 483 | 3.6 | NA | 1,871 | 6.2 | NA | 1,076 | 4.9 | NA | 1,771 | 6.8 | NA | 1,559 | 4.4 | NA | 3,642 | 6.5 | NA |
| 5–14 years | 970 | 7.1 | NA | 2,516 | 8.3 | NA | 2,038 | 9.2 | NA | 1,906 | 7.4 | NA | 3,008 | 8.5 | NA | 4,422 | 7.9 | NA |
| 15–64 years | 8,004 | 58.9 | NA | 17,369 | 57.6 | NA | 11,676 | 53.1 | NA | 14,627 | 56.7 | NA | 19,680 | 55.3 | NA | 31,996 | 57.2 | NA |
| ≥ 65 years | 4,121 | 30.4 | NA | 8,417 | 27.9 | NA | 7,209 | 32.8 | NA | 7,495 | 29.1 | NA | 11,330 | 31.8 | NA | 15,912 | 28.4 | NA |
| Reported a health eventd | ||||||||||||||||||
| Total | 323 | 2.4 | 2.1–2.6 | 957 | 3.2 | 3.0–3.4 | 544 | 2.5 | 2.3–2.7 | 857 | 3.3 | 3.1–3.5 | 867 | 2.4 | 2.3–2.6 | 1,814 | 3.2 | 3.1–3.4 |
| Prevented daily activities or missed school/work | 228 | 1.7 | 1.5–1.9 | 686 | 2.3 | 2.1–2.4 | 398 | 1.8 | 1.6–2.0 | 614 | 2.4 | 2.2–2.6 | 626 | 1.8 | 1.6–1.9 | 1,300 | 2.3 | 2.2–2.5 |
| Medical consultation no absenteeism | 34 | 0.3 | 0.2–0.3 | 56 | 0.2 | 0.1–0.2 | 50 | 0.2 | 0.2–0.3 | 60 | 0.2 | 0.2–0.3 | 84 | 0.2 | 0.2–0.3 | 116 | 0.2 | 0.2–0.2 |
| Prevented daily activities and missed work/school and medical consultation | 61 | 0.4 | 0.3–0.6 | 215 | 0.7 | 0.6–0.8 | 96 | 0.4 | 0.4–0.5 | 183 | 0.7 | 0.6–0.8 | 157 | 0.4 | 0.4–0.5 | 398 | 0.7 | 0.6–0.8 |
CI: confidence interval; NA: not applicable; ND: not determined (question was not asked of this group).
a While the table covers the 155,442 individuals who were enrolled in the survey, the total number of individuals who completed the online safety survey is 91,459.
b Unless otherwise stated (footnote c), percentages are calculated using as denominator the total number of survey participants who completed the online safety survey.
c Percentage among the number of individuals enrolled in the survey for each category (i.e. control or vaccinee in each season).
d A health event was defined by the respondent as of sufficient intensity to cause a medical consultation or work/school/day care absenteeism/prevent daily activities, or both.