Figure 1.
Ferrets’ nasal wash titers after challenge with VN1203. Post‐challenge virus titers of ferrets vaccinated with (A) VN1203 (clade 1), (B) DKHUN795 (clade 2.1), (C) ancestral A antigen, or (D) ancestral D antigen are expressed as mean log10 EID50/ml (horizontal lines) ± standard error (vertical lines). Vaccinated ferrets are represented by black (challenged at 1 year) and gray (challenged at 5 months) circles. Control (PBS‐vaccinated) animals are represented by red (challenged at 1 year) and green (challenged at 5 months) symbols. All control ferrets died or were euthanized before day 7 post‐challenge.