TABLE 26.
Clinical and virologic features of influenza infection in experimentally challenged human volunteersa
| Challenge strain | No. of volunteers challenged | % infected participants with: |
||
|---|---|---|---|---|
| Virus shedding | Clinical illness | Fever | ||
| Influenza A(H1N1) | 532 | 93.1 | 69.3 | 30.9 |
| Influenza A(H3N2) | 473 | 92.5 | 62.3 | 39.5 |
| Influenza A(H2N2) | 86 | 83.9 | 77.4 | 100 |
| Influenza B | 189 | 81.5 | 62.5 | 7.0 |
a
Virus shedding was observed in >80% of infected volunteers. Different challenge strains produced somewhat different clinical features. The most variable symptom was fever, which varied from 7 to 100%. Adapted from Carrat et al. (649).