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 coverage can vary dramatically across regions, with some areas having better access than others

An equity impact analysis of the 2016 Ethiopia Demographic and Health Survey dataset identified significant disparities in full immunization coverage across different regions of Ethiopia among children aged up to 36 months. Children in the Addis Ababa and Dire Dawa regions of Ethiopia were 7 times more likely to have full vaccination coverage compared to children living in the Afar region, a rural region with large numbers of pastoralist nomadic communities.

Geweniger A, Abbas KM. 2020. Childhood vaccination coverage and equity impact in Ethiopia by socioeconomic, geographic, maternal, and child characteristics. Vaccine. 38(20).

Children in rural-urban migrant populations in China, India, and Nigeria have lower immunization rates, requiring special efforts to improve vaccination rates and reduce health inequities and disease outbreaks

According to a systematic review and meta-analysis, children who are rural-urban migrants in China, India and Nigeria were less likely to be fully-immunized by the age of one year than non-migrant urban residents and the general population. These inequities in vaccination rates — often concealed in national averages — call for special efforts to improve immunization rates in this rapidly growing sub-population to reduce both health inequities and the risk of infectious disease outbreaks in the wider society.

Awoh AB, Plugge E. 2016. Immunisation coverage in rural-urban migrant children in low and middle-income countries (LMICs): a systematic review and meta-analysis. Journal of Epidemiology and Community Health. 70(3).

Children in Shanghai whose families migrated from rural areas have lower rates of measles vaccination

Children in Shanghai, China whose families migrated from rural areas — now roughly 40% of the city’s total population — are half as likely as “local” children to receive the first dose of measles vaccine by 9 months of age and 42% less likely to receive the second measles dose by 24 months. The lower rates of timely first dose measles vaccination among rural migrants vs. local children — 78% vs. 89% – – are a key obstacle to measles elimination in China. This indicates a need to specifically target non-local children for vaccination, especially those living in primarily migrant communities.

Wagner AL, Sun X, Huang Z et al.. 2016. On-time measles and pneumococcal vaccination of Shanghai children. Pediatric Infectious Disease Journal. 35(10).

Children living in urban slums may be more likely to miss immunizations due to frequent moves

Children living in urban areas in India were significantly more likely to be only partially immunized compared to children in rural areas. In this study, the authors suggest this may be the result of the tendency for those living in urban slums to move frequently, resulting in only partial immunization. No significant difference was found in rates of non-vaccination (children receiving no vaccines) in rural versus urban communities.

Prinja, S., Monga, D., Rana, S.K., et al.. 2018. District level analysis of routine immunization in Haryana State: implications for Mission Indradhanush under Universal Immunization Programme. Indian Journal of Community Medicine. 43(3).

Immunization coverage can vary greatly between regions within a country

Full immunization coverage, within the Democratic Republic of Congo, varies drastically by region. In the province with the lowest coverage, approximately 5% of children were fully immunized, while in the province with highest coverage, over 70% of children were fully immunized.

Acharya P., Kismul H., Mapatano, M.A., et al.. 2018. Individual- and Community-level Determinants of Child Immunization in the Democratic Republic of Congo: A Multilevel Analysis. PLOS One. 13(8).

Despite improvements, girls and rural children in India still face disadvantages in healthcare and education

In an analysis of of data from India’s National Family Health Survey showed that, despite a decline in urban-rural and gender differences over time, girls and children residing in rural areas remained disadvantaged. Moreover, regions that had the lowest gender inequality in 1992 observed an increase in gender difference over time. Similarly, urban-rural inequality increased in one region during the data collection period.

Singh, P.K.. 2013. Trends in Child Immunization across Geographical Regions in India: Focus on Urban-Rural and Gender Differences. PLoS ONE. 8(9).

Children living in slum conditions have greater risk of illness and less access to immunization

Children in slum settings have higher burdens of vaccine-preventable disease (one study found children in slums in Manila, Philippines were 9 times more likely to have tuberculosis than other urban children) and lower rates of immunization (a study in Niger found 35% coverage in slums vs. 86% in non-slum urban areas).

Unger, A.. 2013. Children’s health in slum settings. Archives of Disease in Childhood. 98(10).

Globally, children living in urban areas are more likely to be fully immunized than children living in rural areas

Globally, coverage of the third dose of DTP is 8% higher among urban dwellers compared to children raised in a rural environment.

Hinman, A.R., and McKinlay, M.A.. 2015. Immunization equity. Vaccine. 33(2015).