Table 2.
Geometric mean concentrations (GMC) of serotype specific IgG titres taken 4 weeks following the PCV‡ primary series, and at 9 and 12 months of age, by number of PCV doses administered in the primary series
| Serotypes | 3 PCV (n=1251) | 2 PCV (n=146) | 1 PCV (n=121) | 0 PCV 3,4 (n=62) | ||
|---|---|---|---|---|---|---|
| GMC (95%CI) | GMC (95%CI) | 3 vs 2 p value2 | GMC (95%CI) | 3 vs 1 p value2 | GMC (95%CI) | |
| 4 weeks post primary series | ||||||
| 4 | 5.47 (4.84–6.19) | 5.23 (4.46–6.13) | 0.661 | 2.20 (1.80–2.70) | <0.001 | 0.04 (0.03–0.04) |
| 6B | 1.66 (1.33–2.07) | 0.86 (0.70–1.07) | <0.001 | 0.19 (0.16–0.22) | <0.001 | 0.11 (0.10–0.13) |
| 9V | 4.76 (4.19–5.40) | 4.71 (3.88–5.71) | 0.933 | 0.90 (0.74–1.09) | <0.001 | 0.07 (0.06–0.08) |
| 14 | 5.51 (4.50–6.76) | 3.12 (2.42–4.03) | <0.001 | 1.07 (0.89–1.27) | <0.001 | 0.34 (0.27–0.43) |
| 18C | 3.20 (2.66–3.86) | 2.67 (2.16–3.31) | 0.22 | 0.58 (0.45–0.74) | <0.001 | 0.06 (0.05–0.07) |
| 19F | 5.52 (4.79–6.36) | 7.99 (6.62–9.64) | 0.003 | 0.84 (0.70–1.00) | <0.001 | 0.25 (0.21–0.30) |
| 23F | 2.93 (2.39–3.59) | 1.65 (1.29–2.11) | <0.001 | 0.23 (0.20–0.27) | <0.001 | 0.11 (0.10–0.14) |
| 9 months | (n=37) | (n=49) | (n=43) | |||
| 4 | 0.79 (0.55–1.14) | 0.86 (0.67–1.12) | 0.682 | 0.60 (0.42–0.85) | 0.277 | NA |
| 6B | 0.82 (0.58–1.17) | 0.81 (0.59–1.12) | 0.949 | 0.39 (0.29–0.52) | 0.001 | NA |
| 9V | 0.91 (0.71–1.16) | 1.00 (0.72–1.38) | 0.661 | 0.56 (0.40–0.77) | 0.021 | NA |
| 14 | 3.99 (2.86–5.57) | 1.93 (1.20–3.09) | 0.02 | 1.11 (0.79–1.57) | <0.001 | NA |
| 18C | 0.49 (0.37–0.65) | 0.41 (0.33–0.53) | 0.353 | 0.18 (0.14–0.24) | <0.001 | NA |
| 19F | 1.04 (0.70–1.54) | 1.40 (1.05–1.86) | 0.207 | 0.89 (0.61–1.29) | 0.568 | NA |
| 23F | 0.65 (0.46–0.94) | 0.44 (0.33–0.60) | 0.094 | 0.24 (0.18–0.32) | <0.001 | NA |
| 12 months | (n=113) | (n=142) | (n=1145) | (n=59) | ||
| 4 | 0.48 (0.41–0.57) | 0.47 (0.40–0.54) | 0.73 | 0.63 (0.50–0.81) | 0.066 | 0.07 (0.06–0.09) |
| 6B | 0.86 (0.72–1.03) | 0.76 (0.63–0.92) | 0.356 | 0.57 (0.46–0.71) | 0.005 | 0.14 (0.12–0.17) |
| 9V | 0.59 (0.51–0.67) | 0.62 (0.54–0.71) | 0.522 | 0.50 (0.41–0.62) | 0.221 | 0.09 (0.07–0.11) |
| 14 | 2.38 (1.98–2.86) | 1.52 (1.26–1.84) | 0.001 | 1.16 (0.94–1.44) | <0.001 | 0.19 (0.16–0.24) |
| 18C | 0.32 (0.27–0.38) | 0.24 (0.21–0.28) | 0.011 | 0.17 (0.15–0.20) | <0.001 | 0.06 (0.05–0.08) |
| 19F | 1.05 (0.83–1.34) | 1.14 (0.95–1.36) | 0.592 | 0.93 (0.76–1.15) | 0.462 | 0.46 (0.35–0.59) |
| 23F | 0.54 (0.44–0.66) | 0.42 (0.35–0.50) | 0.07 | 0.26 (0.21–0.31) | <0.001 | 0.07 (0.06–0.09) |
Three bloods not available for testing
Two sample t test was applied to compare GMC following 2 doses or a single dose of PCV with the GMC following 3 doses of PCV
Two sample t test was applied to compare GMC following a single dose of PCV with the GMC following 0 doses of PCV. For all serotypes the p-value was <0.001 except for serotype 23F at 12 months of age whereby the p-value was 0.042.
Two sample t test was applied to compare GMC following 0 doses of PCV with the GMC following 3 doses of PCV. For all serotypes and all time points the p-value was <0.001.
One blood not available for testing
NA Not applicable