Abstract
INTRODUCTION: in January 2021, a national COVID-19 vaccine campaign was launched in Morocco. The national pharmacovigilance system was strengthened to assess any adverse events related to the COVID-19 vaccine. The objective of this study was to analyse the factors associated with severe Adverse Events Following Immunization (AEFI) related to COVID-19 vaccines in the Casablanca-Settat region in Morocco. METHODS: this multicentric, cross-sectional study was conducted among individuals who reported AEFI after COVID-19 vaccines. Factors associated with the occurrence of severe AEFI were analysed using logistic regression. RESULTS: a total of 1257 reports (2538 AEFI) were analysed. The AstraZeneca vaccine was responsible for 65% of the AEFI. 74% of cases occurred after the first dose, and 92% were considered non-serious. Among the 95 serious cases, 51% presented their first AEFI within 24 hours of vaccination. Age ≥65 years (OR = 2.63; p < 0.001), male gender (OR = 1.75; p = 0.03), and a number of AEFI per patient ≥3 (OR = 2.08; p < 0.001) were associated with serious AEFI. CONCLUSION: although the majority of cases were non-serious, this study highlights the importance of vigilance, particularly for at-risk populations such as the elderly, men, and patients with a high number of AEFI.