[Analysis of the surveillance system for adverse events following Immunization (AEFI) related to COVID-19 vaccines in Colombia, 2021-2023Análise do sistema de vigilância de ESAVI por vacinas contra a COVID-19 na Colômbia, 2021-2023].

Objective: To describe the functioning of the surveillance system for adverse events following immunization (AEFI) in Colombia using the evaluation tools proposed by the World Health Organization (WHO).

Method: Descriptive study of the performance of the AEFI surveillance system for COVID-19 vaccines between 17 February 2021 and 30 September 2023. WHO indicators for structure, process, and results were adapted.

[Experiences and Challenges of the Ecuadorean National Advisory Commission on Serious Events Supposedly Attributable to Vaccination or Immunization, 2020-2023Experiências e desafios da Comissão Consultiva Nacional sobre Eventos Supostamente Atribuíveis à Vacinação ou Imunização graves do Equador, 2020-2023].

Objective: To describe the experiences of the National Advisory Commission on Serious Events Supposedly Attributable to Vaccination or Immunization (ESAVI) implemented in Ecuador for the period 2020-2023.

Methods: A report analyzing the implementation, operations, and results of the National Advisory Commission on Serious ESAVI in Ecuador was prepared. A quantitative analysis of vaccination records was carried out, as well as a qualitative analysis based on expert interviews, reflecting the direct experiences and operational challenges faced by the members of the Commission.