Figure. . Sections of spleen from Ebola virus (EBOV)-infected animals. Top left, BALB/c mouse, note absence of polymerized fibrin (phosphotungstic acid [PTA] hematoxylin, original magnification X400). Field representative of five of five mice tested. Top right: guinea pig. Note discreet foci of polymerized fibrin (arrows) (PTA hematoxylin, original magnification X400). This field shows infrequent fibrin deposits; most fields in five of five animals examined showed no evidence of polymerized fibrin. Lower left: cynomolgus monkey. Note deposition of polymerized fibrin in red pulp (PTA hematoxylin, original magnification X400). Field representative of 25 of 25 monkeys. Lower right: cynomolgus monkey. Electron micrograph showing abundant fibrin deposits in red pulp (original magnification X5,300). Field representative of 11 of 11 monkeys examined.