Vaccine safety surveillance in South Africa through COVID-19: A journey to systems strengthening.

Background: Surveillance systems for monitoring and reporting adverse events following immunisation (AEFI) and adverse events of special interest (AESI) are vital in understanding safety profiles of post-marketed vaccines. Evaluation of surveillance systems is necessary for systems strengthening. We conducted the first evaluation of the South African AEFI surveillance system in its current form, established in 2018.