Authors’ conclusions: the protection provided by the inactivated influenza vaccine in children declines by four to eight months postvaccination. For matched strains, data suggest that the relative efficacy of the live attenuated vaccine versus the inactivated vaccine in young children increases over time. Relative efficacy against mismatched strains was similar over time. Further research is needed to confirm these findings and to characterize the duration of protection provided by inactivated vaccine in children.
Reviewers’ commentary: it seems that the inactivated virus vaccine produces less protection than the attenuated virus vaccine, especially after the fourth month of vaccination. New studies are needed to know the type of vaccine more suitable for use in children, considering its effectiveness, safety and cost-effectiveness.