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 programs have saved millions of lives, especially among children, and will continue to do so in the future

Increases in vaccine coverage and the introduction of new vaccines into LMICs have had a major impact in reducing mortality. Vaccination programs for ten selected pathogens will have averted an estimated 69 million deaths in 98 low- and middle-income countries between 2000 and 2030. Most of this impact has been concentrated in a reduction in mortality among children younger than 5 years (57% reduction), most notably from measles. These public health gains are predicted to increase in coming decades if progress in increasing vaccine coverage is sustained.

Li X, Mukandavire C, Cucunubá ZM et al.. 2021. Estimating the health impact of vaccination against ten pathogens in 98 low-income and middle-income countries from 2000 to 2030: a modelling study. The Lancet. 397(10272).

Globally, immunization has a high return on investment saving billions of dollars by preventing disability, health costs, and premature deaths

By preventing illness, disability, premature death, lost wages, and other costs, this modeling study found that vaccines against ten pathogens averted $828.5 billion of economic burden in 94 low- and middle-income countries between 2021 and 2030. Immunization programs provided a high return on investment (ROI), with projections for net benefits of vaccine programs estimated at $1,445.3 billion (using a cost-of-illness approach) and $3,371.5 billion (using a value-of-a-statistical-life approach) from 2011 to 2030. For every $1 invested in immunization, there was a return on investment of $20 using cost-of-illness and $52 using a value-of-a-statistical-life approach.

Sim SY, Watts E, Constenla D et al.. 2020. Return On Investment From Immunization Against 10 Pathogens In 94 Low- And Middle-Income Countries, 2011–30. Health Affairs. 39(8).

Screening tests in Italy found high rates of infectious diseases in newly-arrived migrants, emphasizing the need for universal screening

Screening tests given to more than 300 newly-arrived economic migrants and asylum seekers in Italy — the majority from sub-Saharan Africa — found high rates of chronic hepatitis B infection and latent and active tuberculosis (with 8% having signs of current infection or active TB). These findings underscore the important of universal screening for infectious diseases for all newly-arrived migrants.

Cuomo G, Franconi I, Riva N et al.. 2019. Migration and health: a retrospective study about the prevalence of HBP, HIV, HCV, tuberculosis and syphilis infections amongst newly arrived migrants screened at the Infectious Diseases Unit of Modena, Italy. Journal of Infection and Public Health. 12(2).

The arrival of Syrian refugees in Turkey has caused a rise in infectious diseases, including preventable ones like measles

Forced migration due to the Syrian civil war has led to a re-emergence of several infectious diseases in Turkey, including vaccine-preventable diseases, such as measles (930 cases reported among refugees over 4 years), tuberculosis and hepatitis A.

Doyanay M, Demiraslan H. 2016. Refugees of the Syrian civil war: impact on reemerging infections, health services, and biosecurity in Turkey. Health Security. 14(4).

Administering hepatitis B immune globulin to newborns in addition to vaccination prevents more infections and is cost-effective

In a study of different strategies for preventing hepatitis B infections in newborns in a Burmese refugee population with a high infection rate, administering hepatitis B immune globulin to newborns whose mothers test positive through a rapid diagnostic test — in addition to vaccinating all newborns with a birth dose — prevented twice as many infections in newborns than vaccination alone and was cost-effective (while the current strategy of providing immune globulin only after a confirmatory lab test was done was not). Thus, this strategy could be considered for similar marginalized or poor populations.

Devine A, Harvey R, Min AM et al.. 2017. Strategies for the prevention of perinatal hepatitis B transmission in a marginalized population on the Thailand-Myanmar border: a cost-effectiveness analysis. BMC Infectious Diseases. 17(1).

Universal hepatitis B vaccination for newborns in refugee camps is highly cost-effective

Providing a birth dose of hepatitis B vaccine to all newborns (in addition to routine HepB immunization) was found to be a highly cost-effective means of preventing hepatitis B-related deaths in three refugee populations in Africa which are at extremely high risk of hepatitis B infection. Providing a birth dose only to newborns whose mothers test positive on a rapid diagnostic test was less cost-effective than vaccinating all newborns automatically. Thus, universal hepatitis B vaccination of newborns should remain a priority in refugee camps, despite competing humanitarian needs.

Reardon JM, O'Connor SM, Njau JD et al.. 2019. Cost-effectiveness of birth-dose hepatitis B vaccination among refugee populations in the African region: a series of case studies. Conflict and Health. 13(5).

Adding hepatitis B vaccine to routine immunization for refugees in Africa reduces transmission and improves global health security

Adding a birth dose of hepatitis B vaccine to routine immunization of refugees in Africa — who have particularly high infection rates — is a highly cost-effective means of reducing transmission of the infection thus strengthening the overall global health security among these mobile, vulnerable populations.

Reardon JM, O'Connor SM, Njau JD et al.. 2019. Cost-effectiveness of birth-dose hepatitis B vaccination among refugee populations in the African region: a series of case studies. Conflict and Health. 13(5).

Correctional facilities can provide access to health services for incarcerated adolescents at risk of hepatitis B

Studies have indicated that the prevalence of risky behaviors associated with Sexually Transmitted Infections (STIs) and HIV is high among incarcerated adolescents. In the US, most adolescents sentenced to serve time in correctional facilities are offered preventive vaccination against hepatitis B. Medical clinics in correctional facilities provide an ideal environment for adolescents in high risk settings to obtain access to preventive health services. In certain cases, these facilities even overcome barriers such as parental consent by making these adolescents wards of the state and followed by which preventive services are obtained by the state providing consent.

Tedeschi, S.K., Bonney, L.E., Manalo, R., et al.. 2007. Vaccination in juvenile correctional facilities: state practices, hepatitis B, and the impact on anticipated sexually transmitted infection vaccines. Public Health Rep. 122(1).

Cancer survivors experience much higher complications from vaccine-preventable infections

In survivors of pediatric and young adult cancers in the US, the risk of mortality from infectious complications is 4 times higher than in their cancer-naïve siblings. Within the first five years after cancer diagnosis, the risk of some vaccine-preventable infections such as pneumonia and hepatitis is more than 9-fold and 6-fold higher, respectively. More than 5 years after cancer diagnosis, the risk of these two infections remains high at 3.7 and 2.5 times higher than siblings.

Perkins, J.L., Chen, Y., Harris, A., et al.. 2014. Infections among long‐term survivors of childhood and adolescent cancer: A report from the Childhood Cancer Survivor Study. Cancer. 120(16).

Higher vaccine coverage for some vaccines was associated with a lower risk of developing a specific type of leukemia

A study including thousands of children from the U.S. state of Texas found that children born in counties with high coverage of HepB, Polio, and Hib vaccines were 33%, 37%, and 42% less likely to develop a specific type of leukemia than children born in counties with lower coverage of each vaccine.

Pagaoa, M. A., Okcu, M. F., Bondy, M. L., et al.. 2011. Associations between vaccination and childhood cancers in Texas regions. The Journal of Pediatrics. 158(6).