Fig. 5: Histopathology and detection of SARS-CoV-2 RNA in the lungs of challenged Syrian hamsters.

Lung tissues were harvested at 4 days post SARS-CoV-2 challenge from hamsters that were previously vaccinated with PBS, MVA, or MVA-S. Formalin-fixed, paraffin-embedded lung tissues were stained either by hematoxylin and eosin (H&E, a–f) or by a SARS-CoV-2 RNAscope probe (g–l). Pathology scores were determined by a licensed pathologist who viewed 3–4 sections in each study group in a blinded fashion. Panels a–c and g–i are images of all lobes from a representative hamster in each group. Panels d–f and j–l are close-up images from a representative area of panels a–c and g–i, respectively. In panels g–l, the blue color indicates nucleus staining and the red/pink color represents SARS-CoV-2 spike positive-sense (genomic) RNA. The scale bar represents 5 mm (a–c); 6 mm (g–i); and for the rest (d–f, j–l) the bar represents 200 μm.