Figure 2.

Replication and virulence of representative highly pathogenic avian influenza virus (H5N1) viruses in mice and ducks. A) Virus titers in organs of mice that were humanely killed on postinfection day 3 with 10⁶ EID₅₀ of the test viruses. B, C) MLD₅₀ of the indicated viruses. D) Virus titers in organs of ducks that were killed on day 3 post inoculation with 10⁶ EID₅₀ in 0.1 mL of the indicated viruses. E) Virus shedding from ducks on the indicated days after inoculation. F) Death pattern of ducks in the infected and control groups. EID₅₀, 50% egg infectious dose; MLD₅₀, 50% lethal dose for mice.