Schematic model of the YF-induced pathogenesis process, starting from a mosquito bite and leading to hepatic apoptosis and cytokine storm. The pathogenesis process is divided into five distinct steps (noted from 1 to 5), and each tissue compartment into which YFV circulates is displayed in a distinctly colored box. Intense viral replication in the liver is thought to trigger a molecular chain reaction inducing severe cytokine imbalance and pro-inflammatory cytokine secretion, leading to severe vasculopathy and multi-organ dysfunction. DC, dendritic cells; pDCs, plasmacytoid dendritic cells.