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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Armed conflict can lead to outbreaks of polio

An outbreak of wild polio virus began two years after the onset of the civil war in Syria and subsequently spread to Iraq, causing a total of 38 cases (36 in Syria). Factors leading to the outbreak included a decline in polio surveillance and in polio vaccination coverage (from 83% for 3 doses of oral polio vaccine pre-war in Syria to 47-52%).

Mbaeyi C, Ryan MJ, Smith P et al.. 2017. Response to a large polio outbreak in a setting of conflict- Middle East, 2013-2015. Morbidity and Mortality Weekly Report. 66(8).

Collapse of primary healthcare during humanitarian emergencies can lead to infectious disease outbreaks in neighboring areas

The humanitarian emergency in Venezuela, and resulting collapse of its primary health care infrastructure, has caused measles and diphtheria to reemerge — disproportionately affecting indigenous populations — and spread to neighboring countries. This sets the stage for the potential reemergence of polio. The re-establishment of measles as an endemic disease in Venezuela (with >5,500 confirmed cases) and its spread to neighboring countries threaten the measles-free status.

Paniz-Mondolfi AE, Tami A, Grillet ME et al.. 2019. Resurgence of vaccine-preventable diseases in Venezuela as a regional public health threat in the Americas. Emerging Infectious Diseases. 25(4).

A measles outbreak can be costly for national governments

A measles outbreak in the Federated States of Micronesia (FSM) in 2014, causing nearly 400 confirmed cases, cost nearly US$4 million (around US$10,000 per case), 88% of which was for a mass vaccination campaign, outbreak investigations, and other containment costs. While the U.S. government covered 2/3 of the costs, the economic burden to FSM — in labor and other costs of containing the outbreak, the direct costs of illness, and productivity losses — were the equivalent of the country’s entire education budget for one year.

Pike J, Tippins A, Nyaku M et al.. 2017. Cost of a measles outbreak in a remote island economy: 2014 Federated States of Micronesia measles outbreak. Vaccine. 35(43).

Humanitarian emergencies often lead to infectious disease outbreaks, highlighting the importance of immunization

In a study of the overlap between complex humanitarian emergencies and disease outbreaks, researchers found that more than 40% of complex emergencies that occurred between 2005-2014 were associated with an outbreak of infectious disease, with a high likelihood that the outbreak was vaccine-preventable.

Culver A, Rochat R, Cookson S. 2017. Public health implications of complex emergencies and natural disasters. Conflict and health. 11(1).