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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The introduction of PCV13 vaccine in Tennessee reduced racial disparities in pneumococcal disease

Population-based surveillance data collected in the state of Tennessee from 1998 – 2016 found that the introduction of PCV13 was associated with reductions in socioeconomic and racial disparities in PCV13-serotype invasive pneumococcal disease (IPD). PCV13 introduction was associated with the prevention of IPD in the overall population as well as substantial decreases in racial disparities in IPD over time between Black and White populations. Before PCV13 was introduced, Black people in the study had an IPD incidence 1.5 times higher than White people – 24.7 and 16.4, respectively. After PCV13 introduction, Black people had an IPD incidence 1.15 times the incidence among Whites: 15 and 13.1, respectively.

Raman R, Brennan J, Ndi D et al.. 2021. Marked Reduction of Socioeconomic and Racial Disparities in Invasive Pneumococcal Disease Associated With Conjugate Pneumococcal Vaccines. The Journal of Infectious Diseases. 223(7).

A school-based flu vaccination program in California led to higher vaccination rates, fewer absences, and less flu transmission

A school-located influenza vaccination program implemented in 95 preschools and elementary schools in California was associated with increased influenza vaccination coverage, decreased school absences due to illness, and lower influenza transmission across the community. The 11% increase in flu vaccination in children enrolled in target schools was associated with fewer flu hospitalizations in the community, including 160 fewer influenza hospitalizations per 100,000 among people aged 65 and older.

Benjamin-Chung J, Arnold BF, Kennedy CJ et al.. 2020. Evaluation of a city-wide school-located influenza vaccination program in Oakland, California, with respect to vaccination coverage, school absences, and laboratory-confirmed influenza: A matched cohort study. PLoS Medicine. 17(8).

Increasing influenza vaccination coverage by 10% leads to a 65% decrease in antibiotic use

A retrospective analysis of influenza vaccination coverage and antibiotic prescribing rates from 2010 to 2017 across states in the United States, controlling for differences in health infrastructure and yearly vaccine effectiveness, found that a 10-percentage point increase in influenza vaccination coverage was associated with a 6.5% decrease in antibiotic use across all age groups, equivalent to 14.2 fewer antibiotic prescriptions per 1000 individuals.

Klein EY, Schueller E, Tseng KK et al.. 2020. The Impact of Influenza Vaccination on Antibiotic Use in the United States, 2010–2017. Open Forum Infectious Diseases. 7(7).

Influenza vaccination reduces antibiotic prescriptions and helps fight against antibiotic resistance

A study led by researchers from the U.S. Centers for Disease Control and Prevention found that across five winter influenza seasons (2013-2018), vaccination against influenza averted 1 in 25 antibiotic prescriptions among outpatients with acute respiratory illness (ARI). The study population included 37,487 ARI outpatients 6 months or older treated at over 50 healthcare facilities across the United States. The authors conclude that influenza vaccination may curb unnecessary antibiotic use and help reduce the global threat of antibiotic resistance.

Smith ER, Fry AM, Hicks LA et al.. 2020. Reducing Antibiotic Use in Ambulatory Care Through Influenza Vaccination. Clinical Infectious Diseases. 71(11).

Rotavirus vaccination reduces the risk of childhood seizures by 20-34% in the US and Spain

Seizures are the most common non-gastrointestinal symptom associated with rotavirus infection. Studies have found that rotavirus vaccination significantly reduced the risk of childhood seizures during the year following vaccination by approximately 20% for seizures requiring emergency care or hospitalization in the US and by 16-34% for childhood seizures requiring hospitalization in Spain.

Rivero-Calle I, Gomez-Rial J, Martinon-Torres F. 2016. Systemic features of rotavirus infection. Journal of Infection. 72.

Children with critical pertussis have lower scores in language, cognitive, and motor development, highlighting the importance of immunization

More than one-third of children under one year of age in a US study, admitted to a pediatric intensive care unit for critical pertussis had significantly abnormal scores on the Mullen Scales of Early Learning, especially in the area of language development. These children also had a significantly lower mean score for all areas of the test, including cognitive and motor development. This indicates the need for routine neuro-development screening of child survivors of critical pertussis.

The Mullen Scales of Early Learning assesses cognitive and motor development [Gross Motor, Visual Reception, Fine Motor, Expressive Language, and Receptive Language] in children. The Mullen test is generally used for evaluating intellectual development and readiness for school.

Berger JT, Villalobos ME, Clark AE et al.. 2018. Cognitive development one year after infantile critical pertussis. Pediatric Critical Care Medicine. 19(2).

Immunization can prevent long-term effects of meningococcal disease, such as hearing loss and psychological problems

A systematic literature review of studies of the long-term effects of invasive meningococcal disease in high-income countries found that children who survived the disease had a greater incidence of hearing loss and psychological problems, including attention-deficit/hyperactivity disorder (ADHD) than control groups or the general population. In addition, they had increased odds of death – one study showed more than a 25% greater mortality rate in this population than did the general public up to 30 years after having the disease.

Strifler L, Morris SK, Dang V et al.. 2016. The health burden of invasive meningococcal disease: a systematic review. Journal of the Pediatric Infectious Diseases Society. 5(4).

Vaccinated children missed fewer school days compared to unvaccinated children

In a study of school-based influenza vaccination in Los Angeles County, California, children who were vaccinated missed significantly fewer days of school than children who were not (2.8 vs. 4.3 per 100 school days).

Pannaraj PS, Wang HL, Rivas H et al.. 2014. School-located influenza vaccination decreases laboratory-confirmed influenza and improves school attendance. Clinical Infectious Diseases. 59(3).

Immunizing school-aged children against the flu reduces the risk of infection for everyone in the community

School-aged children (5-18 years old) experience the highest attack rates of influenza of any age group and are thus the most important means of spread of infection in the community, making them crucial targets for influenza vaccination. In a study of school-based influenza vaccination in Los Angeles County, California, schools that offered flu vaccine to their students reduced the risk of any child getting the flu by 30% (regardless of vaccination status) compared to schools that did not offer flu vaccine to students.

Pannaraj PS, Wang HL, Rivas H et al.. 2014. School-located influenza vaccination decreases laboratory-confirmed influenza and improves school attendance. Clinical Infectious Diseases. 59(3).

Vaccinating pregnant women with Tdap vaccine protects infants from pertussis and provides additional protection in their first year

A large study in California involving nearly 150,000 newborns found that vaccinating pregnant women with the Tdap vaccine provided 91% protection against pertussis infection among infants under 2 months of age and 88% protection before the infants had any vaccinations. The study also showed that vaccinating mothers during their pregnancy did not reduce the effectiveness of infant vaccination but that maternal Tdap vaccination provided additional protection to the infants through their first year of life.

Baxter R, Bartlett J, Fireman B et al.. 2017. Effectiveness of vaccination during pregnancy to prevent infant pertussis. Pediatrics. 139(5).