Table 2.
Estimates of the Community Probability of Infection and the Secondary Attack Proportion for children and adults
| Persons assumed to be susceptible | Influenza A subtype | Cumulative community probability of infection (per season) | Secondary attack proportion | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Children probability (95%CI) | Adults probability (95%CI) | Children probability (95% CI) | Adults probability (95% C1) | ||||||
| All persons | pH1N1 | 0.18 | (0.12- 0.25) | 0.06 | (0.03- 0.11) | 0.15 | (0.05- 0.28) | 0.07 | (0.00- 0.15) |
| sH1N1 | 0.03 | (0.01- 0.06) | 0.02 | (0.01- 0.04) | 0.06 | (0.00- 0.19) | 0.07 | (0.00- 0.19) | |
| sH3N2 | 0.09 | (0.0-, 0.14) | 0.05 | (0.02- 0.08) | 0.07 | (0.00- 0.17) | 0.09 | (0.03- 0.18) | |
| Persons with antibody ≤1:160 | pH1N1 | 0.18 | (0.12- 0.25) | 0.07 | (0.03- 0.11) | 0.18 | (0.05- 0.33) | 0.08 | (0.02- 0.15) |
| sH1N1 | 0.04 | (0.02- 0.08) | 0.02 | (0.01- 0.05) | 0.10 | (0.00- 0.31) | 0.08 | (0.00- 0.23) | |
| sH3N2 | 0.13 | (0.08- 0.20) | 0.05 | (0.02- 0.08) | 0.14 | (0.02- 0.35) | 0.11 | (0.03- 0.22) | |
| Persons with antibody ≤1:40 | pH1N1 | 0.18 | (0.11- 0.24) | 0.07 | (0.03,-0.11) | 0.18 | (0.05- 0.31) | 0.08 | (0.02- 0.16) |
| sH1N1 | 0.06 | (0.02- 0.12) | 0.02 | (0.01- 0.05) | 0.25 | (0.00- 0.83) | 0.07 | (0.00- 0.21) | |
| sH3N2 | 0.16 | (0.08- 0.28) | 0.06 | (0.03- 0.09) | 0.18 | (0.02- 0.46) | 0.12 | (0.02- 0.26) | |
CI = credibility interval.
1A(H3N2).