Advancing the National Immunization Program in an era of achieving universal vaccine coverage in China and beyond

BACKGROUND

Immunization is a cornerstone of public health. Despite great success, China's National Immunization Program (NIP) faces challenges, such as the integration of several World Health Organization-recommended vaccines and other systemic issues. The Innovation Laboratory for Vaccine Delivery Research (VaxLab), supported by the Bill & Melinda Gates Foundation and established in 2021 at Duke Kunshan University, focuses on enhancing China's NIP through research and policy advocacy. This editorial aims to summarize the key findings of the manuscripts published in the collection contributed by VaxLab team and set the future research agenda.

KEY FINDINGS

The collection contains eleven manuscripts discussing China's immunization landscape and strategies to improve coverage, particularly for non-NIP vaccines like human papillomavirus vaccine (HPV), pneumococcal conjugate vaccine (PCV), Haemophilus influenzae type b vaccine (Hib), and rotavirus vaccines. Key findings include: (i) The COVID-19 vaccination campaign demonstrated China's capacity for rapid, large-scale immunization efforts, suggesting potential for broader vaccine coverage improvements; (ii) Efforts in combating cervical cancer through the HPV vaccine indicate progress but also highlight challenges like vaccine supply and equitable access; (iii) The lag in adopting higher-valent paediatric combination vaccines in China needs attention to address regulatory and health system hurdles; (iv) Disparities in access to non-NIP vaccines underscore the need for government initiatives to improve vaccine coverage, especially for remote areas and marginalized populations; (v) Original studies emphasize the influence of caregivers' knowledge, health workers' financial incentives, and concerns about vaccine efficacy on immunization rates; (vi) Case studies from the Weifang City of China and Indonesia to introduce PCV offer insights on successful vaccine introduction strategies and the impact of innovative financing and government support.

CONCLUSION

The articles emphasize the need for government leadership, strategic policymaking, and public awareness to enhance vaccine coverage and equity. The VaxLab will continue strengthening China's NIP by focusing on vaccine financing, emphasizing diversity, equity, and inclusion, and improving maternal vaccination coverage. Research will extend to Southeast Asian and Western Pacific regions, especially in middle-income countries facing challenges in vaccine financing and delivery. The collective efforts outlined in this collection show a commitment to evolving and adapting immunization strategies to meet global health goals and to provide equitable access to vaccines for all.

Determinants of geographical inequalities for DTP3 vaccine coverage in sub-Saharan Africa

Childhood immunization is one of the most effective health interventions, making it a key indicator of progress towards universal health coverage. In the last decade, improvements in coverage have been made globally, however, slow progress has been documented in sub-Saharan Africa with considerable subnational variations. We explore potential drivers of equitable immunization services based on subnational DTP3 coverage estimates. Using vaccine coverage at the 5 by 5 km area from 2000 to 2016, we quantify inequality using three measures. We assess the shortfall inequality which is the average deviation across subnational units from that with the highest coverage for each country. Secondly we estimate the threshold index, the proportion of children below a globally set subnational coverage target, and lastly, a Gini coefficient representing the within-country distribution of coverage. We use time series analyses to quantify associations with immunization expenditures controlling for country socio-economic and population characteristics. Development assistance, maternal education and governance were associated with reductions in inequality. Furthermore, high quality governance was associated with a stronger relationship between development assistance and reductions in inequality. Results from this analysis also indicate that countries with the lowest coverage suffer the highest inequalities. We highlight growing inequalities among countries which have met national coverage targets such as South Africa and Kenya. In 2016, values for the shortfall inequality ranged from 1% to 43%, the threshold index from 0% to 100% and Gini coefficient from 0.01 to 0.37. Burundi, Comoros, Eswatini, Lesotho, Namibia, Rwanda, and Sao Tome and Principe had the least shortfall inequality (<5%) while Angola, Ethiopia and Nigeria had values greater than 40%. A similar picture was noted for the other dimensions of inequality among these particular countries. Immunization program investments offer promise in addressing inequality, however, domestic mechanisms for resource implementation and accountability should be strengthened to maximize gains in coverage.