Fig. 2.

Direct contact transmissibility of H7 influenza viruses. Three ferrets were inoculated with 10⁷ EID₅₀ of NL/219 (A), NL/230 (B), Tky/VA (C), Can/504 (D), NY/107 (E), or Ck/Conn (F) virus, and nasal washes were collected from each ferret on the indicated days p.i. (dark bars). A naïve ferret was placed in the same cage as each inoculated ferret 24 h p.i., and nasal washes were collected from each contact ferret on indicated days p.c. (light bars). The limit of virus detection was 10^1.5 EID₅₀/ml.