Fig 5. Intramuscular immunization with EV-D68 protects against VANBT challenge.

(A) Schematic representation of infection and immunization regimen. Female cotton rats were mock-immunized i.m. on day 0 and at 3 weeks, infected with VANBT on day 0, or immunized i.m. on day 0 and at 3 weeks with UV-VANBT, ATCC, VANBT, or MO/49 using 10⁶ TCID₅₀/100 μl of virus. At 7 weeks, all animals were challenged i.n. with 10⁶ TCID₅₀ of VANBT and sacrificed at 10 h or 48 h p.i. (B) Viral titers in the nose and lung of animals sacrificed at 10 h p.i. n = 5 per group. Data are representative of two independent experiments. * p<0.05 where each group is compared with mock-immunized group.