Figure 2 shows the number of laboratory confirmed invasive meningococcal disease (IMD) cases that were serogroup B or C (78% of all IMD in Australia in 2013 was identified as serogroup B or C). The Figure shows that at each age group serogroup B is predominant, and nationally, the peak incidence of serogroup B disease was in those less than 5 years, whereas the peak of serogroup C disease was in those older than 45 years.