The Knowledge Hub

What is the Knowledge Hub?

Explore the VoICE Knowledge Hub—a searchable database featuring the latest peer-reviewed research on immunization benefits, especially in low- and middle-income countries. Browse the Knowledge Hub using a variety of different filters to find vaccine evidence based on country, region, topic, or disease. Click on a tag to find more evidence on a specific area, such as the return on investment of vaccines or impacts of infectious disease outbreaks.


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Integrating vitamin A supplementation during vaccine campaigns increased coverage and effectiveness for both interventions

In an effort to reach children with vitamin A deficiency in the African countries of Angola, Chad, Cote d’Ivoire, and Togo, vitamin A supplementation was administered during Polio vaccine campaigns. This led to a minimum coverage of 80% for vitamin A and 84% for polio vaccine in all of the immunization campaigns. During the second year of vitamin A integration into the polio vaccination campaign, coverage exceeded 90% for both vitamin A and polio vaccination in all four countries.

Chebab, E.T., et al.. 2016. Experience of integrating vitamin A supplementation into polio campaigns in the African Region.. Vaccine. 34(43).

Empowering women can lead to greater vaccination rates in children

In a systematic review of qualitative research from low- and middle-income countries, women’s low social status was shown to be a barrier to their children accessing vaccinations. Specific barriers included access to education, income, resource allocation, and autonomous decision-making related to time. The authors suggest that expanding the responsibility for children’s health to both parents (mothers and fathers) may be one important element in removing persistent barriers to immunization often faced by mothers.

Merten, S., Hilber, A.H., Biaggi, C., et al.. 2015. Gender Determinants of Vaccination Status in Children: Evidence from a Meta-Ethnographic Systematic Review.. PloS ONE. 10(8).