Avian Influenza H5N1 in Tigers and Leopards
Figure 1. Histopathologic and immunohistochemical evidence of avian influenza A (H5N1) virus in leopard lung. A) Diffuse alveolar damage in the lung: alveoli and bronchioles (between arrowheads) are flooded with edema fluid and inflammatory cells. B) Inflammatory cells in alveolar lumen consist of alveolar macrophages (arrowhead) and neutrophils (arrow). C) Many cells in affected lung tissue express influenza virus antigen, visible as brown staining. D) Expression of influenza virus antigen in a bronchiole is visible mainly in nuclei of epithelial cells.