Table 4.
Effect of screening case definition on respiratory syncytial virus (RSV) associated annual hospitalization rates (2010–2012)*
| Population under surveillance | Under–2 years (N = 3956) | Under–5 years (N = 9740) | ||||||
|---|---|---|---|---|---|---|---|---|
|
Case definitions |
No. met case definition |
No. of RSV positive cases (%) |
Incidence Rate (IR)† |
IR under–estimation (%) |
No. met case definition |
No. of RSV positive cases (%) |
IR† |
Under–estimation IR (%) |
| All Medical |
386 |
67 (17) |
7.4 |
NA |
484 |
74 (15) |
3.2 |
NA |
| ARI (WHO) |
239 |
60 (25) |
6.6 |
–10% |
299 |
64 (21) |
2.8 |
–14% |
| SARI (WHO) |
90 |
34 (38) |
3.8 |
–49% |
107 |
35 (33) |
1.5 |
–53% |
| SARI (Old) |
35 |
10 (29) |
1.1 |
–85% |
41 |
11 (27) |
0.5 |
–85% |
| ILI (WHO) |
37 |
10 (27) |
1.1 |
–85% |
54 |
14 (26) |
0.6 |
–81% |
| ILI (Old) | 106 | 26 (25) | 2.9 | –61% | 139 | 32 (23) | 1.4 | –57% |
ARI – acute respiratory illness, SARI – severe acute respiratory illness, ILI – influenza–like illness, WHO – World Health Organization
*For incidence rate calculations data for full calendar years were used. Data imputed for 6 weeks surveillance gap between 31 January 2012 and 13 March 2012.
†Per 1000 age–specific population.