Clinical monitoring after intranasal administration of artesunate. On day 5 pi (a), 6 pi (b) or 7 pi (c), mice received a single IN administration of artesunate (20 mg/kg). A control group received IN placebo solution (d) either on day 5 pi, 6 pi or 7 pi. Compared to control group, IN administration of artesunate led to the absence of symptoms development (when treatment had been administered on day 5 pi) or to a reversion of symptoms (when treatment had been administered on day 6 pi or 7 pi). Bienvenu clinical staging scale: Stage 0: asymptomatic mice; stage 1: unspecific symptoms (ruffled fur); stage 2: ruffled fur and motor impairments; stage 3: hemiplegia and/or respiratory distress; stage 4: coma and/or convulsions. Coloured arrows indicates the time of treatment for each group. Each line represents one mouse.