Table 2.

Macroscopic lung lesion score

Score	Severity	Gross findings
0	No	The lung lobes are evenly pink and spongy; the cut surfaces show no fluid, congestion, or hemorrhage
0.5	Minimal	Foam or frothy exudate extends to the trachea or fills the main bronchi, and/or discoloration is present in a lobe, with slight fluid oozing from the cut surface, minimal congestion, or minimal hemorrhage
1	Mild	The cut surface of the lobe is moist, with slight fluid oozing from the cut surface; foam or frothy exudate is generally present, oozing from the cut surface; foam or frothy exudate is also observed in the trachea, with mild congestion or focal/small areas of hemorrhage
1.5	Mild to moderate	The lobe is congested and partially condensed (increased density and firmness); a variable amount of fluid oozes from the cut surface; foam or frothy exudate is present in the trachea, with mild to moderate congestion and multifocal petechial hemorrhages
2	Moderate	The lobe is congested, heavy, and exhibits a mildly condensed consistency; fluid oozes from the cut surface, with moderate congestion and multifocal ecchymotic hemorrhages

Modified from Adam and colleagues.²⁸