| Age groups | Number of cases | Proportion | p-value |
| 0 - 4 years old | 421 | 6.56 |
|
| 5 - 14 years old | 1983 | 30.89 |
|
| ≥15 years old | 3987 | 62.1 | 0.001 |
| Unspecified | 29 | 0.45 |
|
| Total | 6420 | 100 |
|