| Value | Category | Cases | |
|---|---|---|---|
| 1 | 2003 | 40 | 
                                    
                                    0.6%
                                 | 
| 2 | 2002 | 51 | 
                                    
                                    0.7%
                                 | 
| 3 | 2001 | 10 | 
                                    
                                    0.1%
                                 | 
| 4 | 2000 | 9 | 
                                    
                                    0.1%
                                 | 
| 5 | Before 2000 | 27 | 
                                    
                                    0.4%
                                 | 
| 6 | Not vaccinated | 6826 | 
                                    
                                    98%
                                 | 
| Sysmiss | 5963 |