Table 3.
Adverse event rates and relative risks by age group, pregnancy and concomitant vaccine status
| Group | Type of adverse event* | ||||||||
| Any adverse event (n/N (%)) | Fever (n/N (%)) | Medical attendance (n/N (%)) | |||||||
| Influenza vaccine+concomitant vaccine(s) | Influenza vaccine alone | Relative risk (95% CI)† |
Influenza vaccine+concomitant vaccine(s) | Influenza vaccine alone | Relative risk (95% CI)† |
Influenza vaccine+concomitant vaccine(s) | Influenza vaccine alone | Relative risk (95% CI)† |
|
| 6 months to 4 years | 189/1295 (14.6) |
333/4885 (6.8) |
2.1 (1.8 to 2.5) |
58/1211 (4.8) |
82/4768 (1.7) |
2. 8 (2.0 to 3.9) |
15/1295 (1.2) |
44/4885 (0.9) |
1.3 (0.7 to 2.3) |
| 5–14 years | 33/295 (11.2) |
262/4120 (6.4) |
1.8 (1.3 to 2.5) |
9/281 (3.2) |
45/3985 (1.1) |
2.8 (1.4 to 5.7) |
2/295 (0.7) |
19/4120 (0.5) |
1.5 (0.3 to 6.3) |
| 15–39 years | 205/2612 (7.8) |
631/10 822 (5.8) |
1.4 (1.2 to 1.6) |
27/2491 (1.1) |
94/10 529 (0.9) |
1.2 (0.8 to 1.9) |
18/2612 (0.7) |
57/10 822 (0.5) |
1.3 (0.8 to 2.2) |
| 40–64 years | 138/1516 (9.1) |
1395/20 193 (6.9) |
1.3 (1.1 to 1.6) |
27/1456 (1.9) |
163/19 497 (0.8) |
2.2 (1.5 to 3.3) |
19/1516 (1.3) |
75/20 193 (0.4) |
3.4 (2.1 to 5.6) |
| ≥65 years | 568/4710 (12.1) |
1127/23 444 (4.8) |
2.5 (2.3 to 2.8) |
89/4439 (2.0) |
120/22 783 (0.5) |
3.8 (2.9 to 5.0) |
33/4710 (0.7) |
44/23 444 (0.2) |
3.7 (2.4 to 5.9) |
| Pregnant‡ | 57/634 (9.0) |
61/1384 (4.4) |
2.0 (1.4 to 2.9) |
7/602 (1.2) |
13/1361 (1.0) |
1.2 (0.5 to 3.0) |
2/634 (0.3) |
8/1384 (0.6) |
0.6 (0.1 to 2.6) |
| Total | 1133/10 428 (10.9) |
3748/63 464 (5.9) |
1.8 (1.7 to 2.0) |
210/9878 (2.1) |
504/61 562 (0.8) |
2.6 (2.2 to 3.1) |
87/10 428 (0.8) |
239/63 464 (0.4) |
2.2 (1.7 to 2.8) |
*Denominators differ between any adverse event/medical attendance and fever because reports of fever are solicited in an online survey following the initial short message service (SMS) regarding an adverse event following immunisation (AEFI), and not all participants complete the survey.
†Relative risk of any adverse event, fever or medical attendance for influenza vaccine administered with any concomitant vaccine(s) as compared with influenza vaccine administered alone.
‡Pregnant participants are also included in their respective age categories (age range: 15–49 years).