May 04, 2019 Volume 393Number 10183p1773-1910
Local trends in immunisation coverage across Africa
Alexandre de Figueiredo, Fredrick Were
… In The Lancet, Jonathan Mosser and colleagues7 report estimates of diphtheria-pertussis-tetanus (DPT) vaccine coverage across the African continent at highly localised scales. With use of large-scale public health data from 49 African countries between 2000 and 2016, the authors identified local heterogeneities in DPT coverage and dropout between the first (DPT1) and third (DPT3) doses of the programme. The authors highlighted regions with persistently low coverage and high vaccine dropout rates and assessed coverage with a focus on the 80% coverage target for administrative-level units set by the Global Vaccine Action Plan (GVAP). Although geospatial models have been used previously for subnational coverage estimation in Africa,8 this analysis represents a major leap in both the breadth (a continental analysis) and the volume of data used.
Mosser and colleagues used almost 1 million immunisation records from 49 African countries by use of 183 household surveys hosted at the Global Health Data Exchange. Local coverage estimates were obtained with a Bayesian geostatistical model allowing coverage to be inferred at spatiotemporal points across Africa. Through this inference of yearly, spatially resolved estimates, Mosser and colleagues revealed novel insights in the geographical distribution of DPT coverage across Africa…