TABLE 3.

Pathogenicity of wild-type and mouse-adapted H1N1 influenza viruses in ferrets

H1N1 virusNo. of ferrets showing indicated clinical sign of disease/total no.Nasal wash titer (log10 EID50/ml, mean ± SD) on indicated dpib
Weight loss (%)aSneezing35
A/CA/04/093/3 (8.8 ± 1.6)1/35.4 ± 1.14.5 ± 0.8
A/CA/04/09-MA13/3 (9.7 ± 1.8)1/35.6 ± 0.93.6 ± 1.4
A/TN/1-560/093/3 (5.8 ± 1.8)2/34.9 ± 0.83.9 ± 0.4
A/TN/1-560/09-MA13/3 (7.3 ± 1.9)1/35.7 ± 1.03.8 ± 0.5
  • a The maximum change in the mean value (percentage)±SD observed over a period of 14 days after inoculation is shown in parentheses.

  • b Virus was not detected in any group tested 7 dpi (detection limit, <0.75 log10 EID50/ml).