Lochlainn LMN, de Gier B, van der Maas N, et al. - Via performing a systematical review of the available evidence, researchers examined how the administration of the first dose of measles-containing vaccine (MCV1) to infants younger than 9 months influence their immune responses to subsequent MCV doses. They identified 351 records as eligible for full-text screening and 21 records as eligible for inclusion in the review. Findings suggest the achievement of high seropositivity, vaccine effectiveness, and T-cell responses in correlation to administering MCV1 to infants younger than 9 months followed by additional MCV doses; these effects are identified to be independent of the age at MCV1. This supports vaccinating very young infants in high-risk settings. However, some evidence indicated achievement of lower antibody titres after one or two subsequent doses of MCV among infants who received MCV1 at an age younger than 9 months vs those who received measles vaccination at age 9 months or older.