Global, regional, and national vaccination coverage and immunization system indicators in 195 countries from 1980-2016

Vaccinations have made enormous contributions to global public health over the past several decades. Increases in vaccination coverage have played a large role in the declines seen in child mortality over the Millennium Development Goal (MDG) period. However, vaccine-preventable diseases are still responsible for nearly quarter of annual child deaths. In conjunction with the transition to the Sustainable Development Goal (SDG) period, the Global Vaccine Action Plan (GVAP) outlined an integrative framework to continue progress towards achieving universal vaccination coverage. Robust estimates of routine and new vaccination coverage are essential for assessing global, regional, and country level progress towards reaching the SDG and GVAP targets. To date, estimates produced jointly by the WHO and UNICEF serve as the main source of coverage estimates for both public and private organizations in the global health community. However, limitations in their methodology limit the accuracy and interpretation of these estimates. In this study, we seek to fill in these gaps by using robust modeling techniques to estimate vaccination coverage for all new and routine vaccinations recommended by the WHO for 195 countries from 1980 to 2016. We additionally estimate comprehensive and comparable estimates of an overall vaccine indicator (estimated as a geometric mean across all vaccinations), drop-out, timeliness, and administrative bias at the global, regional, and country level.