g, Geometric mean + s.e.m. viral titres of WNV-infected mousebrains day 6 post-infection. Values represent combined data for 12-20 mice per treatment group from 10 to 12 litters. Data in c and f represent combined survival probabilities for three and four independent litters, respectively, in each group. Similar results were observed in each independent experiment. *P 0.05; **P 0.01; ***P 0.001; NS, not significant; t-test. 