Figure 2.

Detection of influenza viremia in influenza H3N2-infected ferrets. Three ferrets were infected with 10⁶ egg infectious dose (EID₅₀) of influenza A H3N2 virus intranasally and followed up for 6 days, with bleeds prior to infection and at days 1, 2, 4, and 6. RNA was extracted from whole blood samples and was tested for influenza RNA by (A) reverse-transcription polymerase chain reaction (RT-PCR) assay #1 or (B) transcription-mediated amplification (TMA). Line denotes S/CO = 1. The experiments were each performed once.