FIG. 2.

Virulence and immunosuppressive activity of recombinant CDVs in ferrets. The five viruses are color coded: 5804P, black; SLAMblind, green; Cko, blue; Vko, red; VCko, orange. (A and B) Each box represents one animal, each experimental group consisted of four animals, and results from each individual animal are always shown in the same sequence from left to right. For the virulence index (A), black represents the highest score (3), white represents the lowest score (0), and intermediate shades of gray represent a score of 2 or 1. For the immunosuppressive index (B), black is 2, gray is 1, and white is 0. Leuko. #, leukocyte number. Lymph. p., lymphocyte proliferation. N Ab, neutralizing antibodies. (C to F) Dots indicate the onset of rash. In animals euthanized for humane reasons, the time of death is indicated by a triangle. In animals that recovered, the time of rash healing is indicated by a diamond. The time course of infection (each pair of symbols represents one animal) and number of animals without rash (C), number of CDV-infected cells per million PBMC (D), leukocyte number (E), and in vitro proliferation activity of lymphocytes from infected animals (F) are shown. Days p.i. are indicated on the x axes, and the number of CDV-infected cells per million PBMC, leukocyte number, or proliferation activity is indicated on the y axis. Dotted lines or broad gray lines indicate threshold levels used for determination of the immunosuppressive index value. Error bars indicate standard deviations. TCID₅₀, tissue culture 50% infective dose; leuko, leukocyte.