Ultra- and micro-structural changes of respiratory tracts in SARS-CoV-2 infected Syrian hamsters

Table 1 SARS-CoV-2 specific criteria of histopathologic examination scoring

Organ	Type of lesions	Representative lesions
Trachea	Lamina Propria Submucosa	Inflammatory cell infiltration Edema
	Lumen	Potein-rich exudate Cellular exudate; inflammatory cell Cellular exudate; desquamated cell debris Hemorrhage
	Epithelium	Inflammatory cell infiltration Morphological change of epithelial cell Loss of epithelial cilia Loss of intercellular integrity Detached epithelium from basement membrane
Lung	Inflammation
	Peribronchiolar	Inflammatory cell infiltration Parabronchiolar inflammation
	Perivascular	Inflammatory cell infiltration Hyperemia
	Bronchiole lumen	Protein rich exudate Cellular exudate Floating detached epithelial cell Infiltrate into alveolar space
	Bronchiole epithelium damage	Morphological change of epithelial cell Loss of epithelial cilia Detached epithelium from basement membrane
	Interstitial pneumonia	Thickened alveolar wall Inflammatory cell infiltration into alveolar wall Proportion of lesion
	Hemorrhage	Blood leakage from vessels into perivascular region alveolar space

Each parameter has a range of 0 to 3 by its severity or proportion.
0: normal or under 10%; 1: mild or 10 to 40%; 2: moderate or 40 to 70%; 3: severe or over 70%.
The sum of score may represent the severity of each organ.

ISSN: 1297-9716