Fig 9. Comparison of airborne transmission of HK and R5 in ferrets.
Groups of two ferrets were inoculated intranasally with 106 TCID50 of recombinant viruses HK (top panels) and R5 (bottom panels) containing all eight gene segments of A/Hong Kong/1/1968. One naïve ferret was co-housed with each inoculated ferret in a separate transmission cage starting from one day after inoculation. Data show results of two replicate experiments performed on different days. Lines depict viral titers in nasal swabs (empty circles) and throat swabs (closed circles) collected from inoculated ferrets. White and black bars depict viral titers in nasal and throat swabs, respectively, of the indirect contact ferrets. Numbers show titers of hemagglutination inhibiting antibodies in the blood collected from the indirect contact animals 2 weeks post exposure.