While some studies suggested a protective role of the TLR3 system against WNV [38] and its antagonizing by NS1, important for WNV virulence [33], others have demonstrated that the TLR3 system is required for allowing WNV entry into the brain, thus representing a preconditional system for the development of lethal encephalitis [39]. The gene discussed is TLR3; the disease is encephalitis.