Table 3.
Rates of seroconversion and seroprotection 1 week and 4 weeks after single dose of the influenza vaccine, as measured by HI assay.
| Immunogenicity end point | A/California/7/2009 (H1N1)
|
A/Victoria/210/2009 (H3N2)
|
B/Brisbane/60/2008
|
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Heroin users | Methadone users | Non user controls | p value | Heroin users | Methadone users | Non user controls | p value | Heroin users | Methadone users | Non user controls | p value | |
| No. of subjects | 10 | 11 | 20 | 10 | 11 | 20 | 10 | 11 | 20 | |||
| Baseline | ||||||||||||
| Seroprotection, % (95% CI) | 10.0 (0.3, 44.5) | 27 (6.0,61.0) | 20 (5.7, 43.7) | 0.61 | 40 (12.2, 73.8) | 45 (16.8, 76.6) | 25 (8.7, 49.1) | 0.47 | 0 (–, –) | 18 (2.3, 51.8) | 25 (8.7, 49.1) | 0.23 |
| Postvaccination day 7 | ||||||||||||
| Seroprotection, % (95% CI) | 90.0 (55.5, 99.8) | 82 (48.2, 97.7) | 65.0 (40.8, 84.6) | 0.28 | 90.0 (55.5, 99.8) | 82 (48.2, 97.7) | 80.0 (56.3, 94.3) | 0.79 | 40.0 (12.2, 73.8) | 55 (23.4, 83.3) | 50.0 (28.1, 71.9) | 0.79 |
| Seroconversion, % (95% CI) | 90 (55.5, 99.8) | 55 (23.4, 83.3) | 60 (36.1, 90.9) | 0.17 | 60 (26.2, 87.8) | 45 (16.7, 76.6) | 55 (31.5,76.9) | 0.79 | 40 (12.2, 73.8) | 27 (6, 61.0) | 30 (11.9, 54.3) | 0.80 |
| Postvaccination day 28 | ||||||||||||
| Seroprotection, % (95% CI) | 90.0 (55.5, 99.8) | 91 (58.7, 99.8) | 90.0 (68.3, 98.8) | 0.99 | 80* (44.4, 97.5) | 82 (48.2, 97.7) | 95.0 (75.1, 99.9) | 0.39 | 60.0 (26.2, 87.8) | 64 (35.2, 92.1) | 70.0 (45.7, 88.1) | 0.85 |
| Seroconversion, % (95% CI) | 90 (55.5, 99.8) | 81.2 (48.2, 97.7) | 80 (56.3, 94.3) | 0.79 | 70 (34.8, 93.3) | 73 (39.0, 94.0) | 80 (56.3, 94.3) | 0.81 | 70 (34.8, 93.3) | 45 (16.8, 76.6) | 55 (31.5, 76.9) | 0.52 |