Abstract
BackgroundThe objectives of this review were to evaluate the effect of age at administration of the first dose of a measles-containing vaccine (MCV1) on protection against measles and on antibody response after one- and two-dose measles vaccinations.MethodsWe conducted a systematic review of the PubMed/MEDLINE, Embase, Web of Science and Cochrane databases (1964–2017) to identify observational studies estimating vaccine effectiveness and/or measles attack rates by age at first vaccination as well as experimental studies comparing seroconversion by age at first vaccination. Random effect models were used to pool measles risk ratios (RR), measles odds ratios (OR) and seroconversion RR of MCV1 administered at < 9, 9–11 or ≥ 15 months compared with 12 or 12–14 months of age.ResultsWe included 41 and 67 studies in the measles protection and immunogenicity analyses. Older age at MCV1, from 6 to ≥15 months, improved antibody response and measles protection among one-dose recipients. Pooled measles RR ranged from 3.56 (95%CI: 1.28, 9.88) for MCV1 at < 9 months to 0.48 (95%CI: 0.36, 0.63) for MCV1 at ≥15 months, both compared to 12–14 months. Pooled seroconversion RR ranged from 0.93 (95%CI: 0.90, 0.96) for MCV1 at 9–11 months to 1.03 (95%CI: 1.00, 1.06) for MCV1 at ≥15 months, both compared to 12 months. After a second dose, serological studies reported high seropositivity regardless of age at administration of MCV1 while epidemiological data based on few studies suggested lower protection with earlier age at MCV1.ConclusionsEarlier age at MCV1 decreases measles protection and immunogenicity after one dose and might still have an impact on vaccine failures after two doses of measles vaccine. While two-dose vaccination coverage is most critical to interrupt measles transmission, older age at first vaccination may be necessary to keep the high level of population immunity needed to maintain it.
Highlights
The objectives of this review were to evaluate the effect of age at administration of the first dose of a measles-containing vaccine (MCV1) on protection against measles and on antibody response after one- and twodose measles vaccinations
We aimed to evaluate the effect of age at administration of First dose of a measles-containing vaccine (MCV1) on protection against measles and antibody response after one- and two-dose measles vaccinations through a systematic review of observational studies estimating vaccine effectiveness (VE) and/or measles attack rates (AR) by age at first vaccination as well as experimental studies comparing seroconversion risk by age at first vaccination
We conducted a systematic review of the literature following the Cochrane Handbook for Systematic Reviews of Interventions [20] methodological recommendations, and we reported our results according to the Preferred Reporting Items for Systematic Reviews and MetaAnalyses (PRISMA) statement [21]
Summary
The objectives of this review were to evaluate the effect of age at administration of the first dose of a measles-containing vaccine (MCV1) on protection against measles and on antibody response after one- and twodose measles vaccinations. The first dose of measles-containing vaccine (MCV1) is currently administered from 9 to 18 months of age, with vaccination recommended as early as 6 months in specific situations [14,15,16]. Uzicanin and Zimmerman [17] reported a VE of 84 to 93% after one and of 94% after two doses of vaccine. They presented VE summary point estimates for one dose administered at 9–11 (77%) or ≥ 12 months (92%). In order to control measles or to maintain measles elimination, public health stakeholders have to decide on best vaccination schedules based on their country’s epidemiology, health system characteristics and best evidence on the effect of age at vaccination
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
