Table 1.
Heterogeneous clinical and pathological outcomes following SARS-CoV-2 infection.
| Animal | Clinical findings | Clinical score | Pathology findings | Pathology score | Ranking |
|---|---|---|---|---|---|
| NC34 | Severe reduction in SpO2, moderate tachypnea, and severe hypothermia just prior to euthanasia for severe respiratory distress at 8 days post-infection. Less than 24 h earlier, the only abnormality was a moderate reduction in SpO2. Radiography appeared unremarkable until euthanasia when moderate to severe alveolar pattern with a lobar sign and air bronchograms in right lung fields was observed | 9 | Bronchointerstitial lung pattern in all lobes that was most severe in the right caudal lung lobe. Microscopically all lung lobes exhibited similar changes with the right caudal and right accessory lung lobe being the most severely affected. The lung lesions were comprised of diffuse alveolar damage with hyaline membrane formation, type II pneumocyte hyperplasia, and rare multinucleated giant syncytia. Some regions showed early evidence of organizing pneumonia and fibrosis | 19 | 1 |
| NC33 | Severe reduction in SpO2, severe tachypnea, and severe hypothermia just prior to euthanasia for severe respiratory distress at 22 days post-infection. Less than 24 h earlier, the only abnormality was a mild reduction in SpO2. Radiography appeared unremarkable until euthanasia when moderate to severe alveolar pattern in right middle/caudal lung fields and mild alveolar pattern left caudal lung fields were observed | 10 | Severe diffuse alveolar damage of the right lower lung lobe. Other lobes exhibited suppurative alveolar infiltrate with lesser fibrin and edema. The right lung lobe contains peracute to acute lesions of necrosis, fibrin, and hemorrhage with minimal cellular infiltrate | 14 | 2 |
| GH99 | Transient cough beginning on 15 days post-infection. Radiography showed significant changes at 11 days post-infection which improved through 27 days post-infection | 1 | Severe bronchopneumonia of the right lower lung with granulomatous to pyogranulomatous inflammatory response | 10 | 3 |
| NC38 | Minor intermittent reductions in SpO2 | 0 | Mild interstitial pneumonia with low numbers of multinucleated giant cells and rare atypical pneumocyte hyperplasia | 8 | 4 |
| HD09 | Mild focal increase opacity ventral lung field at 11 days post-infection | 1 | Minimal to mild inflammation scattered throughout the lungs | 9 | 5 |
| HB37 | Intermittent mild to moderate pyrexia from 1 to 21 days post-infection with mild dehydration from 14 to 21 days post-infection | 1 | Proliferative lymphocytic vasculitis and proliferative vasculopathy in the right middle lung lobe. Scattered interstitial inflammation throughout the remaining lung lobes | 5 | 6 |
| FR04 | Unremarkable | 0 | Bronchioles exhibited multifocal, mild mineralization | 6 | 7 |
| NC40 | Minor intermittent reductions in SpO2 | 1 | Minimal changes within the lungs. Mild multifocal thickening of the alveolar septa in the right lower lobe associated with a mild inflammatory infiltrate | 4 | 8 |
Clinical findings are summarized for the duration of infection. Clinical scores, pathology findings, and pathology scores reflect measurements at the time of necropsy. Rankings were determined based on a combination of the clinical findings and scores throughout the duration of infection and the pathology findings and scores at the time of necropsy (1 = severe; 8 = mild).
SpO2 = oxygen saturation.