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 saves money by preventing complications and long-term health issues like hearing loss

An analysis of current measles vaccination program in the eastern Chinese province of Zhejiang (which provides 1 dose of measles-rubella vaccine at 8 months of age and 1 dose of MMR at 18 months) estimated that, for every dollar spent on immunization, the health system saves $6.06 in treatment costing, including the costs of treating complications and long-term sequelae, such as hearing loss.

Zeng Y, Luo M, Chen J et al.. 2019. An economic evaluation of the current measles vaccination program: a case study in Zhejiang Province, east China. Vaccine. 37(23).

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).

China could save money by including the Hib vaccine in the national immunization program

If China — one of the few remaining countries in the world that haven’t introduced Hib vaccine in their national immunization program — decides to include the vaccine in their program, it could actually be cost saving; the vaccination costs would be less than the averted costs of illness from Hib meningitis and pneumonia, if a vaccine price matching UNICEF’s (US$2/dose) can be obtained. The vaccination will be cost-effective, but not cost saving, if the program pays the current market price in China of US$10 per dose.

Ning G, Yin Z, Li Y et al. 2018. Cost-effectiveness of the Haemophilus influenzae type b vaccine for infants in mainland China. Human Vaccines & Immunotherapeutics. 14(1).

North Korean refugee children in China have low vaccination rates due to lack of legal status

Children born to North Korean refugee women in China have much lower vaccination rates than local Chinese or migrant children — with full immunization rates of 14% compared to 93% for local ethnic Chinese children and 55% for migrant children. While all ethnic Chinese children are registered and provided with free vaccinations and there are specific programs targeting migrant children, children born to Korean refugees have no legal status and are thus excluded from the public health care system.

Chung HJ, Han SH, Kim H et al.. 2016. Childhood immunizations in China: Disparities in health care access in children born to North Korean refugees. BMC International Health and Human Rights. 16.

Vaccinating infants significantly reduces hospitalizations from pneumonia

According to a study using local epidemiological data in China, vaccinating infants with pneumococcal conjugate vaccine (PCV-13), using a 3+1 schedule, would prevent more than 10 times as many deaths from invasive pneumococcal disease and pneumonia in unvaccinated individuals (147,500 per year) than it would prevent directly in those vaccinated (12,800 per year). This would be due mainly to a reduction in hospitalizations for pneumonia.

Shen K, Wasserman M, Liu D et al.. 2018. Estimating the cost-effectiveness of an infant 13-valent pneumococcal conjugate vaccine national immunization program in China. PLoS One. 13(7).

Vaccinating infants with PCV also reduced disease and hospitalizations in older individuals

The cost-effectiveness of vaccinating infants with PCV-13 in China was estimated to be 21 times greater when the indirect effects of vaccination in reducing invasive pneumococcal disease and hospitalized cases of pneumonia in older (unvaccinated) individuals was taken into account — with costs per quality of life-year gained (QALY) of around US$564 (Y3,777) vs. $11,836 (Y79,204) when only the direct impact on vaccinated children is considered.

Shen K, Wasserman M, Liu D et al.. 2018. Estimating the cost-effectiveness of an infant 13-valent pneumococcal conjugate vaccine national immunization program in China. PLoS One. 13(7).

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).