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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Influenza vaccination for healthcare workers reduced sick days during flu seasons

Healthcare workers who received an influenza vaccine missed fewer days of work compared to non-vaccinated peers (1.74 vs 2.71 days/person). The study took place at a large Italian hospital that employed approximately 5,300 healthcare workers. The researchers examined a severe influenza season (2017/2018) as well as three moderate flu seasons (2010-2013).

Gianino MM, Kakaa O, Politano G et al.. 2021. Severe and moderate seasonal influenza epidemics among Italian healthcare workers: A comparison of the excess of absenteeism. Influenza and Other Respiratory Viruses. 15(1).

Influenza vaccination in patients with diabetes reduces the risk of death and complications

In patients with diabetes, influenza vaccination was associated with a reduced risk of all-cause death, cardiovascular death, and death from acute myocardial infarction (heart attacks) or stroke. The analysis included medical records from 241,551 adult patients in Denmark across nine consecutive influenza seasons (2007 to 2016). Influenza vaccination was associated with a reduced risk for being admitted to the hospital with diabetes-related complications, like diabetic ketoacidosis, hypoglycemia, or coma.

Modin D, Claggett B, Køber L et al.. 2020. Influenza Vaccination Is Associated With Reduced Cardiovascular Mortality in Adults With Diabetes: A Nationwide Cohort Study. Diabetes Care. 43(9).

Introduction of PCV10 reduced antimicrobial use for acute otitis media, saving healthcare costs and combating antimicrobial resistance

The 2010 introduction of PCV10 for infants in Finland led to an estimated 15% reduction among unvaccinated children in purchases of antimicrobials recommended for acute otitis media (AOM), the most common reason for antimicrobial use in many countries. The indirect effects of PCV10 introduction contribute to health care savings and may also help to combat antimicrobial resistance.

Palmu AA, Rinta-Kokko H, Nohynek H et al.. 2020. Indirect Impact of Ten-valent Pneumococcal Conjugate Vaccine Program on Reducing Antimicrobial Use and Tympanostomy Tube Placements in Finland. The Pediatric Infectious Disease Journal. 39(9).

Influenza vaccination reduces absenteeism among healthcare workers

In a retrospective cohort study among healthcare workers (HCWs) of an Italian academic healthcare trust during the 2017–2018 influenza season, non-vaccinated HCWs lost 2.47/100 person-days of work compared to 1.92/100 person-days of work among vaccinated HCWs (p < 0.001). This adds further evidence that absenteeism among HCWs is negatively correlated with influenza vaccination.

Antinolfi F, Battistella C, Brunelli L et al.. 2020. Absences from work among healthcare workers: are they related to influenza shot adherence?. BMC Health Services Research. 20(1).

A study in Germany found that vaccinating children against influenza reduces infections in the general population

A modelling simulation study in Germany found that routine influenza vaccination coverage of 55% in children of 6 months to 17 years indirectly reduces influenza infections by 26% in the general population through pronounced herd effects. The study authors conclude that targeting children in influenza vaccination campaigns may not only reduce their individual disease burden, but also that of non-vaccinated individuals.

Schmidt-Ott R, Molnar D, Anastassopoulou A et al.. 2020. Assessing direct and indirect effects of pediatric influenza vaccination in Germany by individual-based simulations. Human Vaccines & Immunotherapeutics. 16(4).

Vaccinating both boys and girls against HPV can eradicate cancer-causing types of the virus

A Swedish-Finnish study conducted between 2007-2014 found that vaccinating both girls and boys against HPV (a gender-neutral vaccination strategy) could lead to the eradication of the most common cancer-causing types of the virus through stronger herd immunity. The study randomized HPV vaccination interventions across 33 towns (gender neutral HPV, girls-only HPV, and a control non-HPV vaccination), including 80,000 adolescents between ages 12 and 15. Results of general HPV screening at the age of 19 showed that gender-neutral vaccination prevented HPV infections much more effectively than vaccinating girls only.

Vänskä S, Luostarinen T, Baussano I et al.. 2020. Vaccination with moderate coverage eradicates oncogenic human papillomaviruses if a gender-neutral strategy is applied. The Journal of Infectious Diseases. 222(6).

Immunization during pregnancy reduces the risk of stillbirths and preterm delivery caused by influenza

During the 2009 UK influenza A H1N1 pandemic, pregnant women who contracted influenza were five times more likely to have perinatal mortality (stillbirths) and three times more likely to have a preterm delivery, than were pregnant women who did not contract the virus.

Lim BH, Mahmood TA. 2011. Influenza A H1N1 2009 (Swine Flu) and Pregnancy. The Journal of Obstetrics and Gynecology in India. 61(4).

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.

Immunization with PCV7 and PCV13 in Madrid reduced pneumococcal disease and antibiotic resistance

Following the introduction of PCV7 and later PCV13 in Madrid, Spain, there was a 70% reduction in the incidence of invasive pneumococcal disease in children less than 15 years of age. There was also a pronounced decline in the percentages of penicillin- and cefotaxime-resistant strains of the pneumococcus bacteria. After PCV13 was introduced in 2010, cefotaxime resistance among meningitis patients completely disappeared and both cefotaxime and penicillin resistance among non-meningitis cases declined to very low levels (<3%).

Picazo JJ, Ruiz-Contreras J, Casado-Flores J et al.. 2019. Impact of 13-valent pneumococcal conjugate vaccine on invasive pneumococcal disease in children under 15 years old in Madrid, Spain, 2007 to 2016: the HERACLES clinical surveillance study. Vaccine. 37(16).

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).