Fig 4.

Pathological analyses of the lungs of infected macaques. (A) Infection with Norway3568 virus (panel 1) resulted in moderate to severe bronchointerstitial pneumonia (panel 4) with some minimally affected to unaffected regions (panel 7). Infection with Norway3487 virus (panel 2) resulted in moderate to severe bronchointerstitial pneumonia with severe lung edema and inflammatory changes (panel 5), even in areas with less severe gross changes (panel 8). Lungs derived from a noninfected control animal did not have any gross or histological changes (panels 3 and 6). Arrowheads, gross lesions. Boxes drawn with dotted lines depict the areas shown in the microscopic images. Bars, 200 μm. (B) Pathological severity scores in infected animals on day 7 postinfection. To represent comprehensive histological changes, respiratory tissue slides were evaluated by scoring the pathological changes. The pathological scores were determined for each animal in each group (n = 4 and n = 3 for Norway3487 and Norway3568 viruses, respectively). Error bars denote standard deviations. The mean pathological severity score in the right cranial lung lobe was higher for Norway3487 virus than for Norway3568 virus (Student t test, P = 0.0096).