1996 | 1997 | 1998 | 1999 | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Cases (n) | % | Cases (n) | % | Cases (n) | % | Cases (n) | % | ||||||||
Serogroup B | 123 | 63.4 | 102 | 54.6 | 77 | 70.6 | 113 | 74.8 | |||||||
Serogroup C total | 64 | 33.0 | 77 | 41.2 | 28 | 25.7 | 33 | 21.9 | |||||||
Serogroup C <18 months | 2 | 1.0 | 13 | 7.0 | 4 | 3.7 | 9 | 6.0 | |||||||
Serogroup C 18 months–19 years | 49 | 25.3 | 50 | 26.8 | 13 | 11.9 | 16 | 10.6 | |||||||
Other serogroups | 2 | 1.0 | 1 | 0.5 | 0 | 0 | 1 | 0.7 | |||||||
Non-groupable | 5 | 2.6 | 7 | 3.7 | 4 | 3.7 | 4 | 2.6 | |||||||
Total | 194 | 100 | 187 | 100 | 109 | 100 | 151 | 100 |