Virus load in blood and brain post-infection in vaccinated (10 mice per group) and nine control mice.

BALB/c mice were immunized IM or topical with WNV-DermaVir nanoparticles and four weeks later boosted s.c. with WNV-E protein formulated with Matrix-M1. Two weeks after the boost, the mice were challenged i.p. with a lethal dose of WNV. Two days after the challenge virus titers were determined in blood. Viral load in the brain was determined at the day of euthanasia of the moribund animal or at the end of the experiment in the surviving animals (i.e. 20 days post challenge). The number of WNV RNA copies/sample were determined via RT-PCR.