A Faster Flu Test

A gene chip spots nasty strains of bird flu in hours instead of days

Today, diagnosing bird flu entails a four-day wait for laboratory results. That's an eternity for a germ that could spread across an entire country in that time if it were to become contagious between humans, says University of Colorado chemist Kathy Rowlen. That's why she and her colleagues have designed the "flu chip," a genetic detector the size of a microscope slide that identifies multiple flu strains in less than 11 hours.

Unlike traditional tests, the flu chip doesn't require growing and harvesting the virus in question. Instead technicians extract RNA, a molecular template of DNA, from nasal secretions, amplify them for better readability, and place them on a glass wafer embedded with DNA fragments synthesized to mimic flu strains. If the RNA binds with complementary DNA fragments, indicating a match, the unions glow under a laser scanner, revealing a unique pattern of dots for each flu strain. Rowlen says the chip could be ready in time for next year's flu season.