Figure 4
Detailed histopathology of hamster lungs, 10 days after orotracheal SARS-CoV-2 infection. Hematoxylin and eosin staining, bar 50 µm. (A) Uninfected control, no lung lesion, (B) after 1 * 104.5 TCID50 infection, showing vasculitis (arrow), type 2 pneumocyte hyperplasia and bronchialisation of alveoli (arrowhead), intra-alveolar erythrocytes (asterisk), (C) after 1 * 102 TCID50 infection, with vasculitis (arrow), type 2 pneumocyte hyperplasia and bronchialisation of alveoli (arrowhead) and perivascular infiltrates (asterisk), (D) after 1 * 100 TCID50 infection exhibiting perivascular (arrow) and alveolar (asterisk) infiltrates, type 2 pneumocyte hyperplasia and bronchialisation of alveoli (arrowhead), (E) after 1 * 10−1 TCID50 infection, showing alveolar infiltrates (asterisk), type 2 pneumocyte hyperplasia and bronchialisation of alveoli (arrowhead), (F) after 1 * 10−2 TCID50 infection, with focal alveolar infiltrates (arrow) and edema (asterisk), (G) after 1 * 10−3 TCID50 infection, exhibiting focal hypertrophy/hyperplasia of bronchial epithelium (arrow), (H) after 1 * 10−4 TCID50, with focal alveolar infiltrates (arrow), (I) after 1 * 10−4 TCID50 showing focal perivascular infiltrates (arrow).
