Figure 4: Histopathology sections from infected hamsters stained with hematoxylin and eosin. (a) Hepatitis: Hepatic section demonstrates degeneration of hepatocytes with diffuse periportal infiltration of inflammatory cells and bile stasis (brown spots) in parenchyma. (b) Pneumonitis: pulmonary section with severe edematous, diffuse infiltration of inflammatory cells, and hemosiderin deposits (brown spots) into parenchyma.