West Nile virus is also known to cause a neuroinvasive disease manifesting meningitis, meningoencephalitis, encephalitis, or acute flaccid paralysis, commonly associated with diarrhea/vomiting, weakness, impaired vision, confusion, or drowsiness, and shows elevated levels of proinflammatory cytokines IL4, IL6, and IL10 in serum samples (138). This evidence concerns the gene IL6 and encephalitis.