Background: The optimal schedule and the need for a booster dose are unclear forHaemophilus influenzae type b (Hib) conjugate vaccines. We systematically reviewed relativeeffects of Hib vaccine schedules.Methods: We searched 21 databases to May 2010 or June 2012 and selected randomizedcontrolled trials (RCTs) or quasi-RCTs that compared different Hib schedules (three primarydoses with no booster dose [3p+0], 3p+1 and 2p+1) or different intervals in primary schedulesand between primary and booster schedules. Outcomes were clinical efficacy, nasopharyngealcarriage and immunological response. Results were combined in random-effects meta-analysis.Results: Twenty trials from 15 countries were included; 16 used vaccines conjugated to tetanustoxoid (PRP-T). No trials assessed clinical or carriage outcomes. Twenty trials examinedimmunological outcomes and found few relevant differences. Comparing PRP-T 3p+0 with 2p+0there was no difference in seropositivity at the 1.0μg/ml threshold by six months after the lastprimary dose (combined risk difference -0.02, 95%CI -0.10, 0.06). Only small differences wereseen between schedules starting at different ages, with different intervals between primarydoses, or with different intervals between primary and booster doses. Individuals receiving abooster were more likely to be seropositive than those at the same age who did not.Conclusions: There is no clear evidence from trials that any 2p+1, 3p+0 or 3p+1 schedule of Hibconjugate vaccine is likely to provide better protection against Hib disease than other schedules.Until more data become available, scheduling is likely to be determined by epidemiological andprogrammatic considerations in individual settings.
Comparing Haemophilus influenzae type b Conjugate Vaccine Schedules: Systematic Review and Meta-Analysis of Vaccine Trials
Rutjes A;
2013-01-01
Abstract
Background: The optimal schedule and the need for a booster dose are unclear forHaemophilus influenzae type b (Hib) conjugate vaccines. We systematically reviewed relativeeffects of Hib vaccine schedules.Methods: We searched 21 databases to May 2010 or June 2012 and selected randomizedcontrolled trials (RCTs) or quasi-RCTs that compared different Hib schedules (three primarydoses with no booster dose [3p+0], 3p+1 and 2p+1) or different intervals in primary schedulesand between primary and booster schedules. Outcomes were clinical efficacy, nasopharyngealcarriage and immunological response. Results were combined in random-effects meta-analysis.Results: Twenty trials from 15 countries were included; 16 used vaccines conjugated to tetanustoxoid (PRP-T). No trials assessed clinical or carriage outcomes. Twenty trials examinedimmunological outcomes and found few relevant differences. Comparing PRP-T 3p+0 with 2p+0there was no difference in seropositivity at the 1.0μg/ml threshold by six months after the lastprimary dose (combined risk difference -0.02, 95%CI -0.10, 0.06). Only small differences wereseen between schedules starting at different ages, with different intervals between primarydoses, or with different intervals between primary and booster doses. Individuals receiving abooster were more likely to be seropositive than those at the same age who did not.Conclusions: There is no clear evidence from trials that any 2p+1, 3p+0 or 3p+1 schedule of Hibconjugate vaccine is likely to provide better protection against Hib disease than other schedules.Until more data become available, scheduling is likely to be determined by epidemiological andprogrammatic considerations in individual settings.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
