TABLE 5.

Immune response of healthy adults to two doses of GBS III-TT conjugate vaccine by preimmunization status

Initial antibody concn (μg/ml)	GMC (μg/ml) of type III CPS-specific IgG (95% CI; range) at the indicated mo after primary vaccinationa
	0	1	2	6	21	22	23	25.5
<0.05 (n = 8)	NDb (0.03)	1.1c (0.3–3.7; 0.04–4.4)	1.4d (0.5–3.8; 0.1–4.5)	0.9 (0.3–2.1; 0.07–1.8)	0.5 (0.2–1.1; 0.1–1.2)	4.2 (1.6–10.9; 0.7–24.2)	3.5 (1.3–9.5; 0.7–27.1)	3.1 (1.3–7.1; 0.7–16.5)
>0.05 (n = 28)	0.37b (0.19–0.74; 0.05–10.9)	16.0e (7.6–33.5; 0.12–413)	16.0f (7.9–32.5; 0.25–545)	9.2 (5.0–16.8; 0.56–209)	4.6 (2.4–8.8; 0.21–144)	10.3 (6.2–16.9; 1.1–181)	9.7 (5.8–16.2; 0.7–172)	9.0 (5.5–14.5; 0.65–143)

^aThe first vaccine dose was administered at 0 month, and the second was given 21 months later. 95% CI, 95% confidence interval. 

^bNot detectable (below the level of 0.05-μg/ml detection; 0.025 μg/ml was used for computational purposes). The P value was ≤0.0002 compared with all other time points in the group. 

^cP = 0.12 compared with values at 21 months, and P ≤ 0.02 compared with values at 22, 23, and 25.5 months in this group. 

^dP < 0.03 compared to values at 22, 23, and 25.5 months in this group. 

^eP < 0.0001 compared with values at 21 months, and P ≤ 0.05 compared with values at 22, 23, and 25.5 months in this group. 

^fP < 0.0001 compared with values at 21 months, and P < 0.03 compared with values at 22, 23, and 25.5 months in this group.