RESUMO
The rapid development, introduction, and global uptake of COVID-19 vaccines required countries to have strong pharmacovigilance systems in place to monitor and address adverse events following immunization (AEFIs). These systems provide timely data on vaccine safety that support decisions about the potential risks of vaccine adverse events relative to the benefit of disease prevention. In Ethiopia, the monitoring system was limited by the lack of data being submitted through its passive surveillance system, delays in investigating serious adverse events and conducting causality assessments, and the lack of reporting to the World Health Organization (WHO) global database, VigiBase. In Pakistan, the pharmacovigilance system lacked reporting requirements and guidance documentation, regulatory policies were insufficient, and staff lacked the capacity to evaluate AEFI reports. Several interventions were implemented in both countries to improve pharmacovigilance systems and processes necessary to collect, analyze, and report AEFIs from health care facilities to the national level and facilitate the use of global and national electronic reporting tools. In addition, Pakistan improved the regulatory policy environment and engaged vaccine manufacturers and private sector health facilities in AEFI reporting for the first time in the country. Outcomes include an increased number of COVID-19 vaccine-related AEFIs reported and causality assessments completed, which means that potential safety issues were being analyzed more quickly, comprehensively, and accurately. The number of AEFI reports submitted to VigiBase by Pakistan's regulatory authority more than quintupled from approximately 5,000/quarter in 2021 to 28,555/quarter in 2022. In Ethiopia, by October 2022, 44,000 AEFI reports had been received, and 40 causality assessments completed. In both countries, timely AEFI data review and analysis led to prompt recommendations and regulatory actions, highlighting the far-reaching implications of strengthening the country-level pharmacovigilance systems. These strengthened systems are now in place for use with all vaccines.
