Youssef is a researcher (phytopathologist) at Wageningen Plant Research. She holds a master's degree in plant sciences from the Swedish University of Agricultural Sciences (SLU).

Youssef's current research focuses on diagnosing fruit tree diseases, precisely identifying the causal pathogens, and providing advice for disease management. As a phytopathologist, her role involves designing scientific experiments, sampling, in-vitro analyses of diseased plant samples, in-vitro isolation of plant pathogens in pure cultures, and DNA sequencing of targeted pathogens.

Youssef's future research will focus on disease resistance, studying the epidemiology of plant pathogens, and sustainable disease management.