Table 1. Characteristics of the index patients according to age group.
| Total | 0–6 Yr | 7–12 Yr | 13–19 Yr | 20–29 Yr | 30–39 Yr | ≥40 Yr | ||||||||
| Category | (n = 591) | (n = 158) | (n = 232) | (n = 111) | (n = 32) | (n = 26) | (n = 32) | |||||||
| Number of household contacts (including the index patient) | ||||||||||||||
| Two to three | 229 | (39) | 59 | (37) | 104 | (45) | 31 | (28) | 8 | (25) | 14 | (54) | 13 | (41) |
| Four | 283 | (48) | 82 | (52) | 101 | (44) | 59 | (53) | 16 | (50) | 9 | (35) | 16 | (50) |
| Five or more | 79 | (13) | 17 | (11) | 27 | (11) | 21 | (19) | 8 | (25) | 3 | (11) | 3 | (9) |
| Number of secondary cases in household | ||||||||||||||
| None | 494 | (84) | 127 | (80) | 193 | (83) | 103 | (93) | 28 | (88) | 17 | (65) | 26 | (81) |
| One | 80 | (14) | 25 | (16) | 36 | (16) | 5 | (5) | 3 | (9) | 6 | (23) | 5 | (16) |
| Two | 12 | (2) | 6 | (4) | 1 | (0) | 1 | (1) | 1 | (3) | 2 | (8) | 1 | (3) |
| Three | 5 | (1) | 0 | (0) | 2 | (1) | 2 | (2) | 0 | (0) | 1 | (4) | 0 | (0) |
| Treatment | ||||||||||||||
| Zanamivir | 296 | (50) | 22 | (14) | 149 | (64) | 103 | (93) | 7 | (22) | 6 | (23) | 9 | (28) |
| Oseltamivir | 295 | (50) | 136 | (86) | 83 | (35) | 8 | (7) | 25 | (78) | 20 | (77) | 23 | (72) |
| Time interval from onset of fever to take the first medication | ||||||||||||||
| Less than 48 hours | 571 | (96) | 155 | (98) | 224 | (97) | 105 | (95) | 31 | (97) | 24 | (92) | 32 | (100) |
| 48 hours or more | 20 | (4) | 3 | (2) | 8 | (3) | 6 | (5) | 1 | (3) | 2 | (8) | 0 | (0) |
CI; Confidence interval.