Less than 1% of those infected with West Nile virus show severe neurological symptoms
Most people who become infected with West Nile virus show no symptoms, says Dr. Ashley Sommerhalder, of Bossier Family Medicine. "About 1 in about 250 people who are infected have more severe neurological symptoms. These would include anything from meninigitis, which often has a little stiff neck, to encephalitis, which can be associated with confusion and a change in mental state. And these are the cases that generally become deadly if they become serious."