FIG. 3.

Secondary bacterial infections in ferrets. Ferrets were infected with influenza virus, followed 5 days later by a bioluminescent variant of pneumococcus strain A.166. Daily imaging of live, anesthetized ferrets allowed visualization of secondary bacterial infections. Representative examples from single animals of A) nasopharyngeal colonization, B) sinusitis, and C) otitis media are pictured. The color bar on the right indicates the number of relative light units per pixel measured over 2 min. A posterio-anterior view and two lateral views of a ferret with concomitant sinusitis and otitis media are shown in D).