Histopathology of selected organs from infected gerbils. a, c, and e are representatives of Plasmodium probe in situ hybridization on infected brain, liver and spleen sections with depigmentation respectively. b, d, and f are representative of hematoxylin and eosin staining on infected brain, liver, and spleen sections without depigmentation, respectively. Short thick arrows show PbA-infected RBCs while long thin arrows show Plasmodium pigments (hemozoin). Plasmodium pigments (hemozoin) were removed with 10% ammonium oxide in 70% ethanol after de-paraffin on in situ hybridization slides. Post mortem was performed on 19 gerbils used for clinical assessment and survival tests.