U.S. medical experts say half of those infected with West Nile virus have ongoing health concerns more than a year later, including fatigue and tremors.
The lead author of the study -- Dr. Paul Carson of the University of North Dakota School of Medicine and Health Science -- says patients who were diagnosed with a relatively benign manifestation of West Nile fever are just as likely to suffer later health problems as are those suffering more severe West Nile virus-related illnesses, such as encephalitis or meningitis.
"We were seeing patients coming back long after having had West Nile fever, saying they had ongoing problems," said Carson. "People would say things like 'I'm not myself. I'm more fatigued. I have more trouble with my memory.' "
"I hope this study will raise awareness that West Nile virus poses a substantial public health threat," said Carson. "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."
The study appears in the Sept. 15 issue of the journal Clinical Infectious Diseases.
Copyright 2006 by United Press International
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