Table 2.

Proportion of seropositivity of participants on the dose-response study 8 years after vaccination, by vaccine group.

Group	Seropositive participants (neutralizing antibodies >2.7 log10 mUI/mL)			Total tested	p-value (pair-wise comparisons to the reference vaccine)
	N	%	95% CI	N
27,476 IU	56	82.4	71.2; 90.5	68	Ref
10,447 IU	44	86.3	73.7; 94.3	51	0.563
3013 IU	54	80.6	69.1; 89.2	67	0.793
587 IU	55	93.2	83.5; 98.1	59	0.106
158 IU	40	80.0	66.3; 90.0	50	0.746
31 IU	22	95.7	78.1; 99.9	23	0.172
Total	271	85.2	80.8; 88.9	318

P = 0.159 (All groups).