Table 1.
Number of index patients, inflight attack rates among passengers in the same or different sections as the index patients, seated within or beyond two rows of the index patients, with and without restriction to laboratory-confirmed secondary cases infected with influenza A (H1N1) by flight
| Syndromic | Restricted to laboratory confirmed | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Attack rate | Ratio | P | Attack rate | Ratio | P | No. of index patients | Attack rate | Ratio | P | Attack rate | Ratio | P | ||||
| Reference | No. of index patients | Overall | Same vs. different sections | Within vs. beyond two rows | Overall | Same vs. different sections | Within vs. beyond two rows | |||||||||
| [14] | 1 | 0 (0/141) | NA | NA | NA | NA | NA | NA | 1 | 0 (0/144) | NA | NA | NA | NA | NA | NA |
| [25] (Flight 1) | 1 | 0 (0/91) | NA | NA | NA | NA | NA | NA | 1 | 0 (0/91) | NA | NA | NA | NA | NA | NA |
| [25] (Flight 2) | 1 | 0 (0/87) | NA | NA | NA | NA | NA | NA | 1 | 0 (0/87) | NA | NA | NA | NA | NA | NA |
| [25] (Flight 3) | 2 | 1.1% (1/87) | 1/87 vs. 0/0 (non-tour group member) | Inf | NA | NA | NA | NA | 2 | 1.1%) (1/87) | 1/87 vs. 0/0 | NA | NA | 1/NA vs. 0/NA | NA | NA |
| [20] | 12 | 2.1% (2/97) | 2/97 vs. 0/0 | Inf | NA | 2/57 vs. 0/40 | Inf | 0.23 | 9 | 2.1% (2/97) | 2/97 vs. 0/0 | Inf | NA | 2/57 vs. 0/40 | Inf | 0.23 |
| [23] | 1 | 2.3% (4/176) | 0/24 vs. 4/152 | 0 | 0.43 | 0/11 vs. 4/165 | 0 | 0.25 | 1 | 0.6% (1/176) | 0/24 vs. 1/152 | 0 | 0.69 | 0/11 vs. 1/165 | 0 | 0.79 |
| [31] | 1 | 3.7% (5/135) | 4/85 vs. 1/50 | 2.4 | 0.42 | NA | NA | NA | 1 | 3.7% (5/135) | 4/85 vs. 1/50 | 2.4 | 0.42 | NA | NA | NA |
| [19] (Flight 1) | 10 | 13.5% (24/178) | 13/71 vs. 11/107 | 1.8 | 0.12 | 9/56 vs. 13/122 | 1.5 | 0.31 | 6 | 1.1% (2/178) | 2/71 vs. 0/107 | Inf | 0.08 | 2/32 vs. 0/146 | Inf | 0.002 |
| [19] (Flight 2) | 3 | 4.6% (6/131) | NA | NA | NA | NA | NA | NA | 0 | 0.7% (1/131) | NA | NA | NA | NA | NA | NA |
| [26] (Flight A1, A2) | 1 | 5.6% (8/144) | NA | NA | NA | 3/46 vs. 5/98 | 1.3 | 0.73 | NA | NA | NA | NA | NA | NA | NA | NA |
| [26] (Flight B1) | 1 | 4.3% (4/93) | 4/93 vs. 0/0 | Inf | NA | 3/17 vs. 1/76 | 13.4 | 0.003 | NA | NA | NA | NA | NA | NA | NA | NA |
| [32] | 6 | 4.3% (10/233) | 10/233 vs. 0/0 | Inf | NA | 2/81 vs. 8/152 | 0.5 | 0.32 | 1 | 1.7% (4/233) | NA | NA | NA | NA | NA | NA |
| [16] (Flight 1 and 2) | 1 | 4.2% (9/213) | NA | NA | NA | NA | NA | NA | 1 | 4.2% (9/213) | NA | NA | NA | NA | NA | NA |
| [33] | 1 | 1.8% (5/276) | NA | NA | NA | 1/38 vs. 4/238 | 1.6 | 0.68 | 1 | 1.8% (5/276) | NA | NA | NA | 1/38 vs. 4/238 | 1.6 | 0.68 |
| Total | 42 | 3.7% (78/2082) | 34/690 vs. 16/309 | 0.95 | 0.87 | 20/306 vs. 35/891 | 1.66 | 0.06 | 25 | 1.6% (30/1845) | 9/364 vs. 2/309 | 3.82 | 0.06 | 5/138 vs. 5/589 | 4.27 | 0.01 |
NA, not available.