VoICE : Search Immunization Evidence
The VoICE tool is a compendium of the many direct and downstream impacts of vaccine-preventable disease and immunization. The database contains summary explanations of the link between immunization and each impact, as well as sources of evidence for each link. You can browse the VoICE tool by topic, or use the filters to find results based on topic, disease or vaccine, location and published year.
A strong national immunization program can be leveraged during critical health emergencies to aid in outbreak response.
Key Evidence: The detection of H1N1 influenza virus in Mexico in 2009, and subsequently throughout other countries in the Americas, benefited from the laboratory experience with measles and rubella in the region, leading to the rapid detection of and response to what eventually became a novel pandemic virus.
Sustaining immunization activities and preventing vaccine-preventable outbreaks during conflict can be achieved through preemptive preparedness measures and concerted programmatic and financial support from governments and partners.
Key Evidence: During the conflict in Yemen, efforts spearheaded by WHO, with coordination among partners and effective use of resources, especially GAVI, resulted in continued high pentavalent vaccine coverage decreasing only 3% from 2010 to 2015. Yemen also remained polio-free through 2015 and smoothly introduced two new vaccines (MR and IPV).
Key Evidence: During the humanitarian crisis in the Syrian Arab Republic, the constant support from WHO, UNICEF, and local NGOs resulted in immunizations against VPDs reaching over 90% of children.
The use of vaccines is a critical step in controlling the occurrence of antibiotic-resistant infections.
Key Evidence: The US CDC identifies the use of vaccines as one of the 4 critical steps for controlling the spread of antibiotic resistance.
Conflict and migration can lead to disease outbreaks in diseases previously controlled or eliminated and jeopardize disease control efforts.
Key Evidence: 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%).
Key Evidence: 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 to 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.
Key Evidence: Large measles outbreaks occurred in Lebanon and Jordan, following an influx of Syrian refuges migrating to escape conflict. In Lebanon, the measles incidence increased 200-fold in one year following high migration. There were 2.1 measles cases per million population in Lebanon in 2012; this increased to 411 cases per million in 2013.
Immunization globally provides a key opportunity to control emerging disease outbreaks and prevent the spread of disease across national borders.
Key Evidence: The latest International Health Regulations (IHR) of the World Health Organization updated in 2005 contained several major changes compared to earlier versions. However, the need to report cases of cholera and yellow fever has remained along with an expansion of the concerned disease list. These diseases continue to be critical threats to national and international health security, making immunization against them a vital disease control approach.
Key Evidence: The development and successful implementation of a coordinated, multi-country plan in response to a wild polio outbreak in Syria and Iraq halted the outbreak within 6 months. The response, which involved strengthening acute flaccid paralysis surveillance and more than 70 synchronized mass polio vaccination campaigns in 8 Middle Eastern countries (reaching >27 million children), could serve as a model for responding to disease outbreaks in areas affected by conflict and political instability.
Key Evidence: Conflict in the Eastern Mediterranean Region impacted health infrastructure and compromised the success of the region’s measles elimination goal. At the same time that rates of migration and displacement skyrocketed, the number of measles cases in the region doubled, from 10,072 cases in 2010 to 20,898 in 2015.
Key Evidence: In 2013 nearly all of the 175 cases of measles in the US could be traced back to international importations.
Key Evidence: 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.
World travel can perpetuate the spread of multi-drug resistant strains of disease that could be prevented through immunization.
Key Evidence: TB and pneumococcal infections are two of 18 drug-resistant threats to US health security identified by the CDC in 2013 and are potentially vaccine-preventable. Most antibiotic resistant TB infections in the US occur in people born outside the US.
Vaccine-preventable diseases during pregnancy can have devastating consequences for the mother and her baby.
Key Evidence: Mothers infected with rubella virus during the first trimester of pregnancy can give birth to children with permanent disabilities such as intellectual impairment, autism, blindness, deafness, and cardiac defects. The infection is completely preventable if mothers are vaccinated before pregnancy.
Leveraging infrastructure, personnel and expertise gained through prior polio eradication efforts allows countries to quickly track and control other infectious diseases.
Key Evidence: In the Americas, a platform built to secure polio eradication has been expanded to help track, control, prevent, and monitor immunization impact for measles and rubella. In India, highly trained polio health workers have become the basis for a trained workforce working towards the elimination of measles and rubella and helping ensure India’s certification by WHO for having eliminated maternal and neonatal tetanus.
Introduction of vaccines or strengthening of immunization programs can provide opportunities for increased collaboration between agencies with potential for long-term benefits.
Key Evidence: The American Academy of Pediatrics and the International Pediatric Association were included as partners in the measles and rubella elimination initiative, allowing for more direct collaboration around the interactions of primary health and immunization services and concerns.
Key Evidence: The detection of H1N1 influenza virus in Mexico in 2009, and subsequently throughout other countries in the Americas, benefited from the laboratory experience with measles and rubella in the region, leading to the rapid detection of, and response to, what eventually became a novel pandemic virus.
Antimicrobial-resistant infections are expensive to treat and place an economic burden on families and health systems.
Key Evidence: The US CDC estimates that antibiotic resistant pneumococcal infections in the US add $96 million to the costs of treatment each year.