West Nile Virus
Last year the West Nile virus sickened more than 4,000 people in this country. More than 250 people died. Experts say it's impossible to predict what might happen this year. A panel joins Diane to talk about what's know and not known about this disease and its spread.
entomologist at the United States Army Medical Research Institute of Infectious Diseases
biomedical journalist, editor and contributing writer for the "New York Times Magazine"