Lochlainn LMN, de Gier B, van der Maas N, et al. - In view of the mortality seen among children due to measles, even with the availability of safe and cost-saving measles-containing vaccines (MCVs), researchers examined if benefit could be achieved with increasing the age of first MCV dose (MCV1). They conducted a systematic review and meta-analysis of the benefits and risks of MCV1 in infants younger than 9 months. Among 351 studies eligible for full-text screening, data from 56 studies met all inclusion criteria for analysis. The analysis revealed an increase in the proportion of infants who seroconverted from 50% (95% CI 29–71) for those vaccinated with MCV1 at 4 months of age to 85% (69–97) for those were vaccinated at 8 months. Induction of a good immune response was observed when MCV1 was administered to infants younger than 9 months, whereby an increase in the proportion of infants who seroconverted was noted with a higher age at vaccination. MCV1 administration before 9 months of age was identified as safe and led to the induction of a good immune response in a large proportion of infants, although higher antibody titers and vaccine effectiveness are found when MCV1 is administered at older ages. For reducing measles-related mortality and morbidity, recommending MCV1 administration to infants younger than 9 months seems relevant for those at high risk of measles.