Table 4.
Attack Rate for Different Viruses in 2011–2012 and 2012–2013
| Virus | 2011–2012 (n = 2120) |
2012–2013 (n = 2506) |
P Valuea |
|---|---|---|---|
| Influenza virus | 1.3% | 3.8% | <.0001 |
| A(H3N2) | 1.2% | 1.6% | NS |
| A(H1N1)pdm09 | 0% | 1.0% | <.0001 |
| B/Victoria-like | 0% | 0.2% | .04 |
| B/Yamagata-like | 0.05% | 1.0% | <.0001 |
| Coronavirus | 1.2% | 1.2% | NS |
| hMPV | 1.4% | 0.4% | .0004 |
| RSV | 0.3% | 0.7% | NS |
| Rhinoviruses | 0.6% | 2.3% | <.0001 |
| Parainfluenza virus | 0.2% | 0.6% | .04 |
| Bocavirus | 0.1% | 0.1% | NS |
| Adenovirus | 0.1% | 0.1% | NS |
Abbreviations: hMPV, human metapneumovirus; RSV, respiratory syncytial virus; NS, not significant (P > .05).
aPearson χ2 test.