The Food and Drug Administration has approved the first national trial of a drug to treat West Nile virus, which is quickly spreading west and has infected more than 250 people in a dozen states.
Sold by Schering-Plough as Intron A, the drug is a hepatitis treatment which has been shown by lab tests to be effective against West Nile virus.
West Nile first appeared in the United States in 1999, when seven people infected with it in New York died. Nationwide, the CDC has reported 12 U.S. deaths this year from West Nile, eight of them in Louisiana. As of Tuesday, 253 human cases of the virus had been reported to the CDC this year in 11 states and the District of Columbia.

FDA OKs West Nile therapy trial