Blood Test Debuts to Fight West Nile Virus.

By Diedtra Henderson, The Denver Post Knight Ridder/Tribune Business News

Jul. 1--Colorado's blood supply will get a whole lot safer -- as will the rest of the nation's -- as blood banks today begin using a more sophisticated test to winnow out donations tainted with West Nile virus.

Last year, at least 21 people contracted West Nile after receiving blood transfusions from donors who unwittingly carried the infectious disease.

West Nile posed little risk for the vast majority of people who relied on donated blood in 2002, a year in which a record number of Americans died or were sickened by the virus. On average, less than one blood donation…