Haematoxylin phloxine saffron- stained histopathological sections from mice treated intranasally by artesunate (20 mg/kg). (a) Nasal cavity section. This section shows a nasal fold lined by mucosal epithelium. On the first side, the nasal epithelium is normal with regular ciliary lining cells (red star). On the other side, a little and confined cluster of lymphocytes and neutrophils (blue square) is present and nearby, the epithelium is slightly inflammatory. The underlying lamina propria contains a minor lymphoid infiltrate (black cross). (b) Brain section through a cerebral ventricule (red star). A lymphoid infiltrate is located in periventricular zone (black cross) without any injury of the neighbouring nervous tissue and the ependimocyte border. (c) Brain section. Normal neuron bodies (arrow) are surrounded by neuropil. Dark neurons (arrowhead) are common artifacts characterized as monomorphic contracted and intensively stained neurons. They do not represent degenerating cells.