Assessing vaccine introduction and uptake timelines in Gavi-supported countries: are introduction timelines accelerating across vaccine delivery platforms?

BACKGROUND: Previous studies identified factors influencing regulatory approval to introduction timelines for individual vaccines. However, introduction and uptake timelines have not been comprehensively assessed across the portfolio of Gavi-supported vaccines. METHODS: We analysed median times between introduction milestones from vaccine licensure to country introduction and uptake across six vaccine-preventable diseases (VPDs), three delivery platforms and 69 Gavi-supported countries. Data were gathered from public, partner and manufacturer records. VPDs and prequalified vaccines analysed included Haemophilus influenzae type b (DTwP-HepB-Hib, pentavalent), pneumococcal disease (pneumococcal conjugate vaccine, PCV), rotavirus diarrhoea (rotavirus vaccine, RVV), cervical cancer (human papillomavirus vaccine, HPV), polio (inactivated polio vaccine, IPV) and meningococcal meningitis (meningococcal group A conjugate vaccine, MenA). RESULTS: Median time from first vaccine licensure to first Gavi-supported country introduction across VPDs at a 'global level' (Gavi-supported countries) was 5.4 years. Once licensed, MenA vaccines reached first introduction fastest (campaign=0.6 years; routine immunisation (RI)=1.7 years). Most introductions were delayed. Country uptake following first introduction was accelerated for more recently Gavi-supported RI vaccines compared with older ones. CONCLUSION: Factors accelerating timelines across delivery platforms included rapid product prequalifications by WHO, strong initial recommendations by the WHO Strategic Advisory Group of Experts (SAGE) on Immunization, achieving target product profiles on first vaccine licensure within a VPD and completing several VPD milestones at a global level prior to licensure. Milestones required for introduction in Gavi-supported countries should start prior or in parallel to licensure to accelerate uptake of vaccines delivered through diverse delivery platforms.

Situational assessment of adult vaccine preventable disease and the potential for immunization advocacy and policy in low- and middle-income countries.

By 2050, the number of adults over 65 years of age will be double the under-5 population, and heavily concentrated in low- and middle-income countries. Population growth and increasing life expectancies call for effective healthy aging strategies inclusive of immunization to reduce the burden of vaccine-preventable diseases, improve quality of life, and mitigate antimicrobial resistance. Based on a review of available literature on the pneumococcal disease, influenza, and herpes zoster epidemiology and economic burden, and the health systems and policy barriers for adult immunization, we identified evidence gaps and considerations for prioritizing adult immunization. The body of evidence for adult immunization and the health and economic burden of adult disease is heavily concentrated in high-income countries. The few countries reporting adult immunization policies generally focus on high-risk groups. Despite robust child immunization programs in most countries, adult immunization programs and policies lag far behind and there is a general lack of appropriate delivery platforms. Global adult disease burden and economic costs are substantial but evidence from low- and middle-income countries is limited. There is a need for a strengthened evidence base and political commitment to drive a comprehensive, global technical consensus on adult immunization.

A global agenda for older adult immunization in the COVID-19 era: A roadmap for action.

Given our global interconnectedness, the COVID-19 pandemic highlights the urgency of building a global system that can support both routine and pandemic/epidemic adult immunization. As such, a framework to recommend vaccines and build robust platforms to deliver them to protect the rapidly expanding demographic of older adults is needed. Adult immunization as a strategy has the broad potential to preserve and improve medical, social, and economic outcomes, including maintaining functional ability that benefits older adults, their families, communities, and countries. While we will soon have multiple vaccines against COVID-19, we must recognize that we already have a variety of vaccines against other pathogens that can keep adults healthier. They can prevent simultaneous co-infection with COVID-19, and may favorably impact- the outcome of a COVID-19 illness. Further, administering a vaccine against COVID-19 requires planning now to determine delivery strategies impacting how older adults will be immunized in a timely manner. A group of international experts with various backgrounds from health and aging disciplines met to discuss the evidence case for adult immunization and crucial knowledge gaps that must be filled in order to implement effective policies and programs for older adult immunization. This group, coming together as the International Council on Adult Immunization (ICAI), outlined a high-level roadmap to catalyze action, provide policy guidance, and envision a global adult immunization platform that can be adapted by countries to fit their local contexts. Further meetings centered around the value of adult immunization, particularly in the context of COVID-19. There was agreement that programs to deliver existing influenza, pneumococcal, herpes zoster vaccines, and future COVID-19 vaccines to over a billion older adults who are at substantially higher risk of death and disability due to vaccine-preventable diseases are more urgent than ever before. Here we present a proposed framework for delivering routine and pandemic vaccines. We call upon the global community and governments to prioritize action for integrating robust adult immunization programs into the public health agenda.

Archetype analysis of older adult immunization decision-making and implementation in 34 countries.

The global population of adults over 65 years of age is growing rapidly and is expected to double by 2050. Countries will face substantial health, economic and social burden deriving from vaccine-preventable diseases (VPDs) such as influenza, pneumonia and herpes zoster in older adults. It will be essential that countries utilize several public health strategies, including immunization. Understanding the different approaches countries have taken on adult immunization could help provide future learnings and technical support for adult vaccines within life-course immunization strategies. In this study, we describe the priorities and approaches that underlie adult immunization decision-making and implementation processes in 32 high-and-middle-income countries and two territories ("34 countries") who recommend adult vaccines in their national schedule. We conducted an archetype analysis based on a subset of two dozen indicators abstracted from a larger database. The analysis was based on a mixed-methods study, including results from 120 key informant interviews in six countries and a landscape review of secondary data from 34 countries. We found four distinct archetypes: disease prevention-focused; health security-focused; evolving adult focus; and, child-focused and cost-sensitive. The highest performing countries belonged to the disease prevention-focused and health security archetypes, although there was a range of performance within each archetype. Considering common barriers and facilitators of decision-making and implementation of adult vaccines within a primary archetype could help provide a framework for strategies to support countries with similar needs and approaches. It can also help in developing context-specific policies and guidance, including for countries prioritizing adult immunization programs in light of COVID-19. Further research may be beneficial to further refine archetypes and expand the understanding of what influences success within them. This can help advance policies and action that will improve vaccine access for older adults and build a stronger appreciation of the value of immunization amongst a variety of stakeholders.