FIG. 2.

SBA of serogroup B carriers against all serogroup B meningococcal carriage strains. The SBA titers of individual students colonized by serogroup B meningococci are shown. The MC numbers (MC168 to MC172) are the designations of the serogroup B carriage strains detected in the present survey (Table 2). The arrows indicate the time point(s) at which serogroup B colonization was first detected. The four time points are shown in chronological order as indicated on the figure. Student 9 did not attend the second session; therefore, there is no data for this individual at that time point.