WNV H8912 exhibited a significantly reduced neurovirulence.

<p><i>A.</i> Mice were injected i.c. with different doses of WNV H8912 and monitored twice daily. <i>B–C.</i> Mouse primary cortical neuron/glia cultures were infected with WNV H8912 and its wild-type controls WNV NY99. Viral load at indicated time points post-infection was determined by Q-PCR assay (<i>B</i>) or by plaque assay (<i>C</i>). Data are presented as means ± SEM, n = 3. * <i>P</i><0.05 or **<i>P</i><0.01 compared to WNV NY99-infected cells.