Timing of the fourth dose of RTS,S/AS01 malaria vaccine in perennial settings: a modelling study

A fourth dose delivered between 15- and 21-months of age (corresponding to a 6-12 month interval after the third dose) with high population coverage will likely avert the largest proportion of cases of uncomplicated malaria, severe malaria, and deaths in perennial settings, across transmission intensities. Therefore, the delivery of the fourth dose of the RTS,S/AS01 vaccine can be tailored to country-specific context and linked to existing health touchpoints to ensure adequate coverage of this dose to optimize its impact.