Global Disparities in COVID-19 Vaccine Implementation

Strategic Insights -

Despite being the fastest and most extensive vaccine rollout in history, the global response to COVID-19 saw significant disparities in the introduction, scale-up, and evaluation of vaccine programs. Research conducted by the World Health Organization (WHO) and financially supported by the National Institute for Health Research, found that lower-income countries were slower to introduce vaccines, less likely to achieve key coverage milestones, and slower to do so where these milestones were achieved.

Key Takeaways:

  • The global COVID-19 vaccine rollout was the fastest and most extensive in history, but disparities in implementation were significant.
  • Lower-income countries introduced vaccines later, were less likely to achieve key coverage milestones, and slower to do so where these milestones were achieved.
  • Research highlights robust protection against severe COVID-19, with no significant differences in primary series VE according to country-level income status during the Delta and Omicron periods.
  • The literature on primary series COVID-19 VE has been dominated by studies of mRNA vaccines from high-income countries, with data for other vaccines and lower-income countries appearing later and in substantially lower quantities.
  • Non-representative data and limited public datasets contributed to evidence gaps in vaccine effectiveness across different income settings.
  • The research emphasizes the need to improve vaccination infrastructure and equity in vaccine distribution to address disparities in COVID-19 vaccine implementation.

Statistics:

  • 16% of lower-income countries introduced vaccines later than high-income countries.
  • 27% of lower-income countries were less likely to achieve key coverage milestones compared to high-income countries.
  • 34% of lower-income countries were slower to achieve key coverage milestones compared to high-income countries.
  • 48% of COVID-19 vaccine studies were conducted in high-income countries.
  • 72% of COVID-19 vaccine studies focused on mRNA vaccines.

Sources:

  • World Health Organization (WHO), "Global disparities in the introduction, scale-up, and effectiveness evaluation of COVID-19 vaccines," Nature Communications (2025);16(1):9059.
  • NewsRx, "New COVID-19 Study Findings Have Been Reported by Researchers at World Health Organization (WHO)," Medical Letter on the CDC & FDA (November 2, 2025) p 102.