FIG. 13.3.

Severe acute respiratory distress syndrome coronavirus (SARS). (A) Lung showing interstitial pneumonitis, patchy hyaline membranes and prominent intraalveolar edema. (B) Multinucleated syncytial giant cells can be seen in some cases of fatal SARS. Note absence of discernable viral inclusions. (C) Abundant immunostaining of coronavirus antigen in alveolar pneumocytes. (D) Ciliated epithelial cell in upper airway epithelium containing viral antigens. (E) Electron micrograph showing coronavirus particle. These 80- to 100-nm viral particles are named for the characteristic crownlike fringe on the surface.

(E, courtesy of C.D. Humphrey.)