Fig 5. Influenza virus detection in aerosol samples exhaled by infected ferrets.
Three ferrets each were housed under the designated environmental conditions and were presented with 103.8–105.5 pfu of PN99 (green) or IN11 (orange) virus by aerosol inhalation. On 1, 3 and 5 dpi, aerosol samples were collected from ferrets for 15 minutes of normal breathing (A) and 5 minutes of sneezing stimulation (B) and were segregated based on size (0.65–4.7 μm or >4.7 μm) and then assayed for the presence of infectious influenza virus. Total plaque forming units (pfu) from individual ferrets, n = 3, is shown with the grand mean for each sampling condition.