Figure 3

Protection against orthopoxvirus exposure by Sindbis A33^VACV. BALB/c mice were vaccinated intraperitonealy with 1E + 7 pfu of the indicated viruses: Sindbis A33^VACV, Sindbis pTE or left unvaccinated. Where indicated (Figure 3C), mice were vaccinated by tail scarification with 1X10⁶ VACV-Lister. Two weeks later, the mice were challenged with VACV^-WR (4E + 6 pfu i.n. corresponding to 200LD₅₀) and monitored for mortality (A) and weight loss as a measure of morbidity (B). Pocks on the tails were induced in vaccinated or unvaccinated CD-1 mice 14 days post vaccination by intravenous injection with 1E + 04 pfu of VACV-WR (C). Pocks on the tails were stained with Trypan blue and counted. Vaccinated mice were challenged with ECTV (10 pfu i.n. corresponding to 10LD₅₀) (D, E) or ECTV by i.f.p. injection (30 pfu corresponding to 3 LD₅₀) (F, G). Mice were weighed daily to monitor morbidity and checked for mortality (n = 6 per group for Figures 3 A & B, n = 5 per group for Figure 5C and n = 7 per group for Figures 3D, E, F & G). Error bars represent standard errors of the mean (SEM).