Immunizations across the Life Course to Strengthen Health Security

Recommendations of the CSIS Working Group on Routine Immunizations and Global Health Security

Routine immunization programs can serve as a critical platform for a nation’s global health security strategy, both because they help prevent disease outbreaks and because they have the potential to ameliorate pandemics by ensuring infrastructure and training are in place to rapidly and equitably disseminate vaccines to prevent the transmission of infections within vulnerable populations. While routine immunization programs have historically focused on delivering vaccines to children under the age of two, in an outbreak it is essential to reach people of all ages with disease-preventing tools, including vaccines, as the Covid-19 pandemic made clear. But despite clear evidence that vaccines save lives and offer an exceptional return on investment, the reality is that routine immunization services for adolescents and adults are limited, particularly in low-income countries.

On June 20, Gavi, the Vaccine Alliance, in partnership with the government of France and the African Union, launched a replenishment process seeking $9 billion in new pledges and contributions to support an ambitious plan of work in eligible low-income countries, outlined in Gavi’s new 2026–30 investment opportunity. Gavi estimates that it will need $11.9 billion to reach populations in eligible countries with increased access to existing and new vaccines in line with its goals; it will draw on $2.9 billion in repurposed Covid-19 funds while seeking contributions to close the remaining $9 billion funding gap. Meeting Gavi’s ambitious targets and helping countries promote stability and protect health security by strengthening the access of populations of all ages to vaccines will depend to a considerable degree on whether Gavi secures adequate funding and how effectively Gavi stewards its resources during a period of multiple replenishments and competing global crises.

Since 2000, the United States has been a stalwart donor to Gavi while also supporting routine immunization activities through bilateral programs in priority maternal and child healthcountries. At the June 20 session in Paris, First Lady Jill Biden announced by video that the United States would pledge $1.58 billion to Gavi over five years, an increase over recent U.S. commitments of roughly $290 million per year since 2018. By making an early and increased pledge, the U.S. government signaled the importance it attaches to Gavi’s partnership and the role it sees Gavi playing in both protecting child health and promoting global health security. As Gavi seeks to close its funding gap over the next year, the United States can play a constructive role in advancing global commitments to vaccine delivery across the life course through a set of concrete policy options, including

  • by working closely with Congress to ensure the new U.S. pledge is fully funded and by engaging diplomatically with other donor countries to encourage them to make robust contributions in support of Gavi’s next work phase;
  • by ensuring that U.S.-supported bilateral and multilateral immunization initiatives and the work envisioned for the intensive partnerships on health security outlined in the United States’ new Global Health Security Strategy are aligned, adequately funded, and mutually reinforcing;
  • by supporting initiatives to build vaccine manufacturing and regulatory capabilities, both in the United States and in low- and middle-income countries, to ensure a resilient, reliable, and quality-assured vaccine supply for populations in all countries;
  • by supporting youth groups, civil society organizations, and advocacy associations to make the case to governments that investing in immunizations for people across the life cycle prevents disease, promotes healthy aging and economic productivity, and can ameliorate health crises; and
  • by strengthening the delivery of immunizations within all health programs supported by U.S. investments, with a goal of ensuring that each clinical encounter offers an opportunity to encourage patients and their families regarding immunizations.

When the World Health Organization (WHO) launched the Expanded Program on Immunization (EPI) in 1974, the initiative focused on supporting countries in protecting children against six diseases—tuberculosis, diphtheria, tetanus, pertussis, polio, and measles. Since then, immunizations have saved more than 150 million lives, according to a recent Lancet report. Over the past five decades, the EPI has added an additional seven vaccines to those it recommends that countries provide, including vaccines that target adolescents, such as the human papilloma virus (HPV) vaccine, and others that target older children, adolescents, and adults, such as vaccines that protect against influenza or Covid-19. The EPI also recommends an additional set of vaccines, including those for mpox, malaria, dengue, cholera, respiratory syncytial virus (RSV), and yellow fever, for context-specific deployment, and these similarly target populations over two years of age. Yet despite the incorporation of a variety of new immunization tools for adolescents and adults, along with the adoption of global strategies focused on the life course, such as Immunization Agenda 2030, countries’ tendency to deliver vaccines primarily through pediatric programs creates gaps in protecting the health of older populations and suggests that countries may need support in evolving their EPI programs to manage the technical, operational, and administrative complexities of delivering vaccines to people of all ages.

Katherine E. Bliss
Senior Fellow and Director, Immunizations and Health Systems Resilience, Global Health Policy Center
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Inspired by the momentum generated after several years of focus on immunizations through the global smallpox eradication effort, the EPI, which was approved at the 27th World Health Assembly, highlighted the importance of immunizations to development initiatives. It offered WHO member countries technical guidance and assistance in expanding vaccination programs, but through the 1980s and 1990s, many countries still struggled to secure sufficient financing to procure comparatively expensive vaccines for growing cohorts of infants and young children. This led to the launch of Gavi, the Vaccine Alliance, in 2000, with pooled procurement, market-shaping initiatives, and increased financing for eligible low-income countries, making it possible for many health ministries to purchase and deliver vaccines at a low cost and with a phased cofinancing schedule.

Since the beginning of the twenty-first century, there has been significant progress in increasing immunization coverage worldwide for three doses of the diphtheria, tetanus, and pertussis vaccine, but many Gavi-eligible countries have struggled to sustain access to current vaccines and have faced additional challenges in initiating and scaling up access to vaccines for older children, adolescents, and adults. For example, coverage of the second dose of measles vaccine, offered between 12 and 18 months, has increased steadily since the early 2000s, but regional and subnational gaps in coverage remain. During the Covid-19 pandemic, lockdowns and the diversion of scarce resources to outbreak response led to decreased coverage for many vaccines, including measles. In 2023, there were more than 300,000 cases of measles worldwide, suggesting significant pockets of unimmunized and underimmunized children in diverse regions. Among children under the age of five who were infected, at least 75 percent had not received any doses of measles vaccine, and 99 percent were missing both doses.

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Recent WHO/UNICEF Estimates of National Immunization Coverage data also suggests that many middle-income countries struggle to sustain and increase immunization coverage; the fact that a significant number of “zero-dose children” live in middle-income countries points to an important challenge for health security. Gavi’s middle-income country strategy provides some tailored support for countries that have previously transitioned from eligibility or which were never eligible but which require support for introducing specific vaccines, such as the HPV vaccine. However, the strategy does not cover all middle-income countries, and there are several high-population countries that fall through the cracks. Mechanisms such as the Pan American Health Organization’s Revolving Fund and the Africa Centre for Disease Control and Prevention’s recently approved vaccine procurement initiative can enable regions to negotiate lower prices for bulk purchases than countries might be able to secure from suppliers on their own. The new African Vaccine Manufacturing Accelerator, launched on June 20, will focus attention on catalyzing regional capabilities to produce new products for people of all ages; while this new financing mechanism may make it easier for countries to procure vaccines produced nearby, it also points to the importance of building and reinforcing regional regulatory capabilities to build confidence in locally manufactured products.

Reaching adolescents and adults with routine immunization services will require supporting countries in identifying, prioritizing, and reaching populations beyond infants and young children, who are typically reached in the clinical setting, while conflict and natural disasters complicate the effort to reach people of all ages living in situations of fragility. One challenge is that publicly funded health and social insurance programs may cover services for children and pregnant women, but coverage for adolescents and younger adults is inadequate, with services often limited and the quality of service often unacceptable to those populations. HPV immunization programs have focused on delivering vaccines in settings where adolescents congregate, such as schools or markets. However, reliance in some countries on teachers to encourage students and parents to accept the vaccine points to the importance of ensuring that teachers and other influential voices in the community are well informed about the role the vaccine can play in advancing progress toward eliminating cervical cancer.

Recent experience has demonstrated the success of integrating service delivery across diverse health-focused platforms. For example, during the Covid-19 pandemic, health workers focused on the President’s Emergency Plan for AIDS Relief (PEPFAR) provided Covid-19 vaccines to adults seeking HIV prevention, testing, and treatment, along with their family members, and starting in 2024, PEPFAR-funded programs are delivering HPV vaccines to adolescent girls in 15 countries because of increased evidence that infection with HPV increases the risk of HIV infection.

The delivery of Covid-19 vaccines to adults during the pandemic also demonstrated the utility of providing immunization services beyond the clinical setting to include places where people tend to congregate, such as schools, markets, and religious institutions, not to mention pastures or grazing areas. In many places, Covid-19 vaccination efforts drew on lessons learned from programs focused on strengthening seasonal influenza immunization programs, including efforts to reach health workers and older adults. With the Gavi board’s recent decision to sunset the routine Covid-19 vaccination program by the end of 2025, a focus on increasing the uptake of vaccines that protect against influenza, as well as other seasonal respiratory infections, can ensure that adults are routinely reached with immunization services and advice.

Strengthening program management, governance, and the uptake of novel technologies will also support countries in building their capacities to forecast personnel and storage needs into the future. The United States can support the use and uptake of novel technologies, such as electronic registries, to enable countries to better manage immunization data and predict future cohorts of adolescents or adults who will require outreach with information and education. It will also be important to consider how the immunization supply chain, including cold chain and storage facilities, can be used to expand access to products aimed at adolescents and adults.

With the new Gavi 6.0 Vaccine Investment Strategy including “learning agendas” for new vaccines for tuberculosis and dengue, which will target adolescents, it is an opportune time to ensure robust systems for delivering vaccines to adolescents and adults are in place.


In 2023, following the launch of the CSIS Bipartisan Alliance for Global Health Security, CSIS convened the Working Group on Routine Immunizations and Global Health Security. Following a second year of meetings and discussion regarding opportunities for the United States to expand its support for immunizations across the life course, the working group makes the following recommendations:

  • As Gavi seeks to close its funding gap over the next year, the United States can continue to play a constructive role in promoting health security and advancing global commitments to vaccines across the life course. It can do so by working closely with Congress to ensure that the U.S. pledge of $1.58 billion over five years is fully funded and by engaging diplomatically with other donor countries to encourage them to make robust contributions in support of Gavi’s next work phase.
  • The United States’ new Global Health Security Strategy from April 2024 highlights intensive work with at least 50 partnership countries targeted for intensive support in key technical areas. As the partnerships deepen, it will make sense to ensure alignment among the broad range of health security objectives spearheaded by PEPFAR, the President’s Malaria Initiative (PMI), and other U.S. global health initiatives. Building on the launch of the Bureau for Global Health Security and Diplomacy at the Department of State, the United States should use its position within multilateral fora, including Gavi, the Global Fund, the WHO, and the Pandemic Fund, as well as through bilateral relationships, to advocate for attention to immunizations for people of all ages as a critical element of health security.
  • To ensure a readily available supply of vaccines for distribution to people of all ages, the United States should support efforts aimed at strengthening domestic and regional manufacture of vaccines and related supplies. It should also encourage Gavi and UNICEF, as well as regional procurement agencies, to strengthen and diversify vaccine markets by purchasing locally produced, quality-assured products. Finally, the United States should support efforts to build the capacity of low- and middle-income country governments to manage vaccine regulatory and approval processes in order to expedite access to new products to protect people across the life cycle.
  • The United States can support civil society organizations and advocacy initiatives to ensure that governments understand that their populations want vaccines at older ages and that adolescents and adults can be educated as to why it is important to get vaccines across the life course. Adolescents and the faith community can be mobilized to advocate for greater attention to vaccines for populations over the age of two. Advocates can also make the case to governments, particularly finance ministries, that investing in immunizations for people across the life cycle prevents disease, can ameliorate health crises, saves money, promotes healthy aging, and supports economic development in the long term.
  • Building on lessons regarding the use of the health services beyond immunizations to deliver vaccines, including the use of the PEPFAR platform to deliver Covid-19 and HPV vaccines to clients of care and treatment centers and their families, it will be important to identify opportunities to offer immunizations to patients and family of patients in health programs supported by U.S. investments, with a goal of ensuring that each clinical encounter offers an opportunity to encourage patients regarding immunizations, regardless of whether they have come in asking for vaccines. There may also be opportunities to ensure that other initiatives, such as the new PEPFAR nursing leadership initiative, USAID’s Primary Impact program, and the Biden administration’s Global Health Worker Initiative, train personnel on communicating about vaccines to foster trust and generate demand for them for populations older than two years of age.

By helping to prevent disease outbreaks and strengthening the infrastructure necessary to distribute vaccines equitably and quickly in the event of a pandemic, routine immunization programs can serve as a critical platform for a nation’s global health security. But despite clear evidence that vaccines save lives and offer an exceptional return on investment, routine immunization services for adolescents and adults are limited globally—and particularly in low-income countries. As Gavi launches its replenishment to support a new phase of work, and with the WHO’s EPI celebrating its 50th anniversary this year, it is time for the United States, working with partners, to take additional actions to strengthen vaccine delivery to older children, adolescents, and adults, with the goal of reaching all people in a timely way with effective disease prevention options.

Katherine E. Bliss is a senior fellow and director of immunizations and health system resilience with the Global Health Policy Center at the Center for Strategic and International Studies in Washington, D.C.

This publication conveys a majority consensus of the signatories, who are participating in their individual capacity, not as representatives of their respective organizations. No expert is expected to endorse every single point contained in the publication. In becoming a signatory, experts affirm their broad agreement with the publication’s findings and recommendations. Language included here does not imply institutional endorsement by the organizations that working group members represent.

The CSIS Working Group on Routine Immunizations and Health Security is grateful to Carolina Andrada for research assistance and to Corey Donnelley and Ella Bergendahl for helping to coordinate the group's meetings.

About the CSIS Bipartisan Alliance for Global Health Security

The CSIS Bipartisan Alliance for Global Health Security convenes an esteemed group of members of Congress, senior leaders, and subject matter experts to advance a concrete, forward-leaning agenda for U.S. global health security strategy. It prioritizes coherent, sustained U.S. leadership, ensuring success in the major institutional reforms under way across the executive branch, integration of effort with strong accountability measures, enhanced global coordination, and building new partnerships and alliances through strengthened U.S. diplomacy that systematically advances U.S. national interests, amid intensifying geopolitical competition. Equally critical is building the correct institutional arrangements, including adequate private sector incentives, to bring forward the next generation of technological innovation. The alliance is developing concrete options to strengthen core pandemic preparedness and response capabilities, while exploring the untapped opportunities to better align capabilities across traditional infectious disease programming including on HIV/AIDS, routine immunization, and antimicrobial resistance, among other priorities. Building on the record of prior CSIS initiatives, the alliance delivers recommendations on global health security policy and programs to key decisionmakers in the U.S. Congress, the executive branch, and nongovernmental organizations.

The two-year effort, running from spring 2023 through the end of 2024, is cochaired by Senator Richard Burr, principal policy advisor and chair of the Health Policy Strategic Consulting Practice at DLA Piper and former senator from North Carolina, and Julie Gerberding, MD, MPH, CEO of the Foundation for the National Institutes of Health and former director of the CDC. J. Stephen Morrison, PhD, senior vice president and founder/director of the CSIS Global Health Policy Center, sets the alliance’s strategic direction and directs its work on pandemic preparedness and response. Katherine E. Bliss, PhD, senior fellow and director of immunizations and health systems resilience with the CSIS Global Health Policy Center, directs its work on HIV and routine immunization. Michaela Simoneau, associate fellow, leads the alliance’s secretariat. More information on the alliance can be found on its website at


Fata Acquoi is senior congressional lead for PATH in Washington, D.C.

Ahmed Arale is deputy global director and technical lead with the CORE Group Partners Project.

Katherine E. Bliss is senior fellow and director of Immunizations and Health Systems Resilience with the CSIS Global Health Policy Center.

Bruce Gellin is a professor of medicine (adjunct) at the Georgetown University School of Medicine.

Javier Guzman is director of Global Health Policy and a senior policy fellow with the Center for Global Development.

Irene Koek is the head of global health with the Save the Children Federation.

Rebecca Martin is director of the Global Health Institute at Emory University.

Stephen Morrison is senior vice president and director of the CSIS Global Health Policy Center.

Lois Privor-Dumm is director of adult vaccines with the International Vaccine Access Center (IVAC) at the Johns Hopkins Bloomberg School of Public Health.

Lora Shimp is director of the Immunization Center, International, with JSI.