Estimated impact of RTS,S/AS01 malaria vaccine allocation strategies in sub-Saharan Africa: A modelling study

Abstract

The RTS,S/AS01 malaria vaccine, demonstrating 36% efficacy against clinical malaria in phase III trials, is poised for wider roll-out in 2021. This study investigates the optimal allocation strategy for this vaccine under supply constraints using mathematical modeling. Results indicate that prioritizing countries with high malaria incidence and implementing sub-national allocation can significantly maximize the public health impact. Under realistic vaccine coverage and prioritizing areas with parasite prevalence above 10%, an annual dose constraint of 30 million could avert 4.3 million cases and 22,000 deaths in children under five years old. Sub-national prioritization could allow introduction in almost double the number of countries compared to national prioritization. While prioritizing the three pilot countries (Ghana, Kenya, and Malawi) would reduce impact, this effect diminishes with increasing vaccine supply. The study highlights the importance of informed vaccine distribution strategies to maximize the benefits of this groundbreaking malaria vaccine.