TABLE 4.

Geometric mean avidity indices of anti-PRP IgG antibodiesa

StudyGroupNo. of subjects testedGMAI (95% CI)Statistical difference between groups (P value)b
United States
    PostprimaryDTPa + HBV + OPV + Hib*400.126 (0.106-0.150)0.0794
DTPa-HBV-IPV/Hib400.105 (0.094-0.118)
    PreboosterDTPa + Hib*210.192 (0.143-0.257)0.8164
DTPa/Hib230.183 (0.135-0.250)
    PostboosterDTPa + Hib*340.189 (0.145-0.246)0.8067
DTPa/Hib370.182 (0.136-0.193)
Germany A
    PostprimaryDTPa + Hib330.094 (0.092-0.096)1
DTPa/Hib450.094 (0.094-0.095)
    PreboosterDTPa + Hib210.292 (0.221-0.387)0.0189
DTPa/Hib180.183 (0.138-0.242)
    PostboosterDTPa + Hib310.252 (0.202-0.313)<0.0001
DTPa/Hib590.126 (0.115-0.138)
Myanmar
    PostprimaryDTPw-HBV/Hib2.5250.085 (0.070-0.103)0.2398
DTPw-HBV/Hib250.069 (0.051-0.094)
    PostboosterDTPw-HBV/Hib2.5250.207 (0.167-0.258)0.0744
DTPw-HBV/Hib250.283 (0.214-0.374)
  • a Not evaluated in the Germany B study. Blood samples were collected 1 month after the three-dose primary series and before and 4 to 6 weeks after the booster dose. GMAI, geometric mean avidity index; Hib2.5, Hib vaccine containing 2.5 μg PRP conjugated to TT; OPV, oral poliovirus vaccine. *, OmniHIB.

  • b Two-sided P value using one-way ANOVA to show a difference between groups.