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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Immunization with PCV10 in Mozambique reduced pneumococcal carriage rates in both HIV-infected and uninfected children

Within two years of the introduction of PCV10 in Mozambique, the percent of vaccinated children under five years of age with nasopharyngeal carriage of vaccine strains, declined equally in HIV-infected as in HIV-uninfected children. The vaccine-type carriage rates among both HIV-infected and uninfected vaccinated children after the vaccine was introduced were similar.

Pneumococcal nasopharyngeal carriage can be a precursor of invasive pneumococcal disease.

Sigauque B, Moiane B, Massora S et al.. 2018. Early declines in vaccine type pneumococcal carriage in children less than 5 years old after introduction of 10-valent pneumococcal conjugate vaccine in Mozambique. Pediatric Infectious Disease Journal. 37(10).

Introduction of PCV-10 in Mozambique reduced pneumococcal strains in unvaccinated HIV-infected children by 30%

Two years after the introduction of 10-strain pneumococcal conjugate vaccine (PCV-10) in Mozambique, the percent of unvaccinated children under five years of age who carried pneumococcal strains in the vaccine declined 30% among HIV-infected children, while no significant decline in unvaccinated HIV-negative children was seen.

Sigauque B, Moiane B, Massora S et al.. 2018. Early declines in vaccine type pneumococcal carriage in children less than 5 years old after introduction of 10-valent pneumococcal conjugate vaccine in Mozambique. Pediatric Infectious Disease Journal. 37(10).

Travel distance can become a barrier to vaccine access for women seeking neonatal care

An study using GIS to quantify the percent of pregnant women in Mozambique without access to tetanus toxoid (TT) vaccine at varying distances from health facilities estimated that if women cannot travel more than 5 km to a TT immunization site there will be almost 18,000 neonatal tetanus cases each year that could be prevented, costing the country more than US$362 million in treatment costs and lost productivity. Covering 99% of women with TT will currently require people to travel up to 35 km to obtain an immunization.

Haidari LA, Brown ST, Constenla D et al.. 2016. The economic value of increasing geospatial access to tetanus toxoid immunization in Mozambique. Vaccine. 34(35).

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).

Vaccines are most cost-effective in low income countries

An analysis of the impact of rotavirus vaccine in 25 countries found that the rates of vaccination in all countries were highest and risk mortality lowest in the top two wealth quintile’s coverage. Countries differed in the relative inequities in these two underlying variables. Cost per DALYs averted in substantially greater in the higher quintiles. In all countries, the greatest potential vaccine benefit was in the poorest quintiles; however, reduced vaccination coverage lowered the projected vaccine benefit.

Rheingans, R., Atherly, D., and Anderson, J.. 2012. Distributional impact of rotavirus vaccination in 25 GAVI countries: Estimating disparities in benefits and cost-effectiveness. Vaccine. 30(1).

Vaccine-preventable diarrhea is linked to poor growth

A prospective case-control study conducted in several developing countries found that children with moderate-to-severe diarrhea grew significantly less in length in the two months following their episode compared to age- and gender-matched controls.

Kotloff, K.L., Nataro, J.P., Blackwelder, W.C., et al. 2013. Burden and aetiology of diarrhoeal disease in infants and young children in developing countries (the Global Enteric Multicenter Study, GEMS): a prospective, case-control study. Lancet. 382(9888).

Cholera vaccination can provide indirect protection to unvaccinated individuals through herd immunity

The evidence on cholera disease dynamics suggests that significant herd protection can result from a relatively small number of immunizations, particularly in endemic areas where there is some natural immunity among the population.

Jeuland, M., Lucas, M., Clemens, J.,et al. 2009. A Cost–Benefit Analysis of Cholera Vaccination Programs in Beira, Mozambique. World Bank Economic Review. 23(2).

Cholera vaccine programs were found to be cost-effective across three countries

A multi-site study of cholera vaccination programs found that the vaccine was cost-effective in school- and community-based vaccination programs for children in India, Mozambique, and Indonesia.

Jeuland, M., Cook, J., Poulos, C., et al. 2009. Cost-effectiveness of new-generation oral cholera vaccines: A multisite analysis. Value Health. 23(2).