clipped from: news.yahoo.com 
NEW YORK (Reuters Health) - More than a year after being diagnosed with a West Nile virus infection, nearly half of the patients have ongoing health issues including fatigue, memory problems, headache, depression and tremor, a new study shows.
The study also warns that patients diagnosed with West Nile fever, which has generally been thought to be a relatively benign, self-limited condition, are just as likely to have lingering health issues as patients who develop more severe West Nile virus-related illnesses such as encephalitis or meningitis.
"We knew before that West Nile encephalitis was a serious health threat, but we didn't appreciate how much ongoing morbidity there is for West Nile fever, which is much more common," he said.
New tremor was seen or reported in 10 patients (20 percent); neurological and psychological testing revealed abnormalities of motor skills, attention and executive functions.