Vaccine Update: The Impact of War on Global Vaccination Rates

War and conflict impact a staggering number of children. A total of 473 million children, or 1 in 6 globally, reside in a region impacted by conflict.¹ These areas include Afghanistan, Democratic Republic of the Congo, Iraq, Nigeria, Palestinian territories, Sudan, Syria, Ukraine and Yemen, to name a few. Of children around the world who are unvaccinated or undervaccinated, 40% live in countries affected by conflict. In 2024, an estimated 14.3 million children missed all doses of routine vaccines and almost 20 million infants missed at least one dose of diphtheria-tetanus-pertussis containing vaccine globally; 50% of these children live in conflict-impacted regions.²

The risk to child health is compounded in these areas by overcrowding, poor sanitation and malnutrition, which increase the likelihood of disease. In the Palestinian territory of Gaza, vaccine coverage for two doses of inactivated polio vaccine dropped from 99% in 2022 to 90% in 2024. The region’s water and sanitation systems have been decimated, and in July 2024, circulating variant type 2 poliovirus was detected in sewage.¹ In 35 countries defined as fragile and conflict-affected by the World Bank, 57% have very low or <60% coverage for two doses of measles-containing vaccine, while regional counterparts not in conflict have 90%-100% coverage.¹ Countries impacted by war account for a disproportionate number of global polio and measles cases. These areas make up 12% of the global population, yet account for 67% of polio cases and 39% of measles cases.³ As refugees from war-torn regions cross into other countries, the risks for vaccine-preventable disease outbreaks rise. Children displaced by conflict who are living in refugee camps have lower vaccination rates when compared to host populations, which highlights that conflict impacts not only war-torn countries but also neighboring and host countries.³

In areas of conflict, essential health infrastructure becomes vulnerable to disruption. As an example, since October 2023 more than 80% of Gaza’s health, water and sanitation infrastructure has been destroyed by military conflict.⁴ Challenges include loss of vaccination clinics due to damage or destruction and lack of infrastructure and supplies that are necessary for safe vaccine storage and administration. Even more frightening is the rising risk of violence for health workers attempting to provide lifesaving care in regions that are destabilized. In 2023 there were 24 occasions of health care workers being attacked while working on vaccination campaigns.¹ These attacks not only require the reduction in vaccine program personnel in these areas to ensure their safety but also discourage community members from accessing still-operational programs, due to the perception that they are targets for violence. The destabilization of governments also leads to impaired collaboration with international agencies and inability to prioritize vaccine programs.

The approach to protecting children in regions of conflict with recommended vaccines must be innovative and daring. The United Nations International Children’s Emergency Fund (UNICEF) states that providing vaccines to war zones is one of the most urgent challenges faced by non-governmental organizations and requires “extraordinary skills, courage and resilience.”⁴ Strategies being used to provide immunizations in conflict zones include:

• Alternative dosing schedules, including fractional doses of vaccines to provide some protection when vaccine supply is insufficient.
• Diversifying vaccine delivery strategies such as vaccine staging areas at transit points and international border crossings, vaccine programs in refugee camps and places of worship, and mobile outreach initiatives.
• Integration with other humanitarian services, such as nutrition programs. This integrated approach proved effective in South Sudan during its protracted civil war. An increase in vaccine uptake was shown when families traveling long distances to access food aid were offered vaccination at the same time and location. These strategies can harness the power of existing supply chains, transportation networks and funding sources.
• Engaging with novel partners, like Gavi’s Zero-Dose Immunization Programme that links with a broad range of organizations experienced in working in conflict zones.
• Ensuring safe access for humanitarian workers by constant monitoring of threat levels and delivery routes. Cease-fires for the purpose of providing vaccines and humanitarian aid have proven effective. Recently in Gaza, cease-fires allowed for a mass vaccination campaign for polio vaccine that reached 600,000 children.
• Building community trust is essential, as vulnerable populations have been victimized and are often distrustful of authorities and health care workers. Vaccine programs must be culturally sensitive and gain the trust and partnership of community leaders.¹

The impact of global conflict on child health can feel daunting and insurmountable. UNICEF, the World Health Organization (WHO) and Gavi have called for parents, the general public and governments to strengthen their support for immunizations. Support for ongoing investment in vaccines and global immunization programs is required to reach the goals set forth in the WHO’s Immunization Agenda 2030 (IA 2030).⁵ IA 2030’s central strategy —“to extend the benefits of vaccines to everyone, everywhere—is underpinned by four core principles: it puts people in the centre, is led by countries, implemented through broad partnerships, and driven by data.”⁶ As pediatric health care providers, these principles call us to advocate for vaccines for the patients we directly care for and to use our individual and collective voices to advocate for support of vaccines and immunization programs in these challenging times. National and global vaccine funding cuts, growing geopolitical instability, and rising vaccine misinformation aimed at undermining vaccine efforts all threaten to stagnate 50 years of progress in vaccine-preventable diseases or, worse, to reverse progress, which will lead to an increase in deaths.

“The good news is that we have managed to reach more children with life-saving vaccines. But millions of children remain without protection against preventable diseases, and that should worry us all,” said UNICEF Executive Director Catherine Russell. “We must act now with determination to overcome barriers like shrinking health budgets, fragile health systems along with misinformation and access constraints because of conflicts. No child should die from a disease we know how to prevent.”² The need for coordinated global efforts to protect immunization programs in conflict zones and to uphold vaccination as both a public health priority and a human right remains crucial. For an insightful look into this crucial work, tune in this fall for an award-winning UNICEF documentary, Gaza’s Silent Threat, featuring Dr. Younis Awadallah and humanitarian Fairuz Abuwarda. The trailer can be seen here: https://www.youtube.com/watch?v=JKt4DEU3gHU

References:

1. Reaching every child: immunization during conflict. International Vaccine Access Center (IVAC), Johns Hopkins Bloomberg School of Public Health. VIEW-hub. www.view-hub.org. Accessed July 28, 2025. https://view-hub.org/topics/immunizationinconflict
2. Global childhood vaccination holds steady, yet over 14 million infants remain unvaccinated – WHO, UNICEF. News release. Accessed July 28, 2025. https://www.unicef.org/press-releases/global-childhood-vaccination-holds-steady-yet-over-14-million-infants-remain
3. Ciccacci F, Ruggieri E, Scarcella P, et al. Between war and pestilence: the impact of armed conflicts on vaccination efforts: a review of literature. Front Public Health. 2025;13:1604288. doi:10.3389/fpubh.2025.1604288
4. Gaza’s Silent Threat. Documentary. Accessed July 28, 2025. https://www.unicef.org/stories/films/gazas-silent-threat
5. Increases in vaccine-preventable disease outbreaks threaten years of progress, warn WHO, UNICEF, Gavi. News release. April 24, 2025. Accessed July 28, 2025. https://www.who.int/news/item/24-04-2025-increases-in-vaccine-preventable-disease-outbreaks-threaten-years-of-progress--warn-who--unicef--gavi
6. Immunization agenda 2030: a global strategy to leave no one behind. World Health Organization. April 1, 2020. Accessed July 28, 2025. https://www.who.int/teams/immunization-vaccines-and-biologicals/strategies/ia2030