Can investments in health systems strategies lead to changes in immunization coverage?

Abstract

National immunization programs in developing countries have made major strides to immunize the world’s children, increasing full coverage to 83% of children. However, the World Health Organization estimates that 22 million children less than five years of age are left unvaccinated, and coverage levels have been plateauing for nearly a decade. This paper describes the evidence on factors contributing to low vaccination uptake, and describes the connection between these factors and the documented strategies and interventions that can lead to changes in immunization outcomes. The author suggests that investments in these areas may contribute more effectively to immunization coverage and also have positive spill-over benefits for health systems. The paper concludes that while some good quality evidence exists of what works and may contribute to immunization outcomes, the quality of evidence needs to improve and major gaps need to be addressed.

Keywords::

• developing countries
• health systems
• immunization coverage
• performance-based financing

Financial & competing interests disclosure

L Brenzel is an independent consultant who has provided consultative advice to the Bill & Melinda Gates Foundation on health systems strengthening through the GAVI Alliance. She has collaborated with colleagues of the GAVI HSS Technical Advisory Group namely Mickey Chopra, Olusoji Adeyi, and Robert Steinglass, on development of an initial framework on HSS investments and immunization outcomes. She acknowledges partial financial support from the BMGF in the development of this paper. The opinions expressed in this paper represent those of the author alone, and do not reflect the opinions of the BMGF. The author has no other relevant affiliation of financial involvement with any organization or entity with a financial interest in or financial conflicts with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Immunization systems, including routine immunization programs and supplementary immunization activities are a subsystem of the broader health system. Investments in strategies to improve immunization coverage and equity can also strengthen health systems.

• Both demand- and supply-side factors influence the use of vaccination services and completion of the vaccination series in low-income countries. Evidence suggests that maternal education, household socioeconomic status, perceived provider competence, reliability of services and local vaccination cultures are important factors affecting vaccine uptake and completion of the vaccination series. Several of these factors can be addressed through interventions that have demonstrated impacts on coverage.

• There is a growing body of evidence that suggests that community- and household-level strategies (such as patient reminders and use of lay health workers) and strategies to strengthen health systems (such as improved supervision and household incentives) have positive effects on immunization coverage. Facility-based performance-based financing strategies are associated with coverage increases, but more robust studies do not find significant effects.

• There are gaps in the current evidence-base on effective interventions for achieving immunization coverage in low-income countries. Further research on the effect of the private sector, health insurance and risk pooling mechanisms, text messaging, training, facility-based health education and performance-based financing on increasing immunization coverage in low-income settings should be prioritized. The role of quality improvement and strengthened information and logistics systems also need to be investigated.

Notes

¹Search terms included: Immunization coverage, Vaccination coverage, Low income, Developing country, Immunization coverage improvement, Health systems, Health systems strengthening, Training, Performance-based financing; Results-based financing; Conditional cash transfers; Supervision; Community-based strategies; Integration; Decentralization; Information; Health information systems; Quality assurance; Infrastructure (buildings, vehicles); Logistics systems; Supply chain; Outreach; Mass media; Health education and health promotion; Health insurance; Community-based insurance; Vaccination laws; Vaccination regulation; Vaccination governance; Leadership and Management.