Blood test could help stem spread of "superbugs"

November 12, 2013

There’s a significant difference between a bacterial infection and a viral infection, and, apparently, not discerning the difference has serious consequences. Although their symptoms are comparable to those of bacterial infections, viral infections cannot be treated by antibiotics like your typical Z-Pak. So when a patient sick with a virus takes an antibiotic, it allows certain bacteria in the body to strengthen and mutate. According to the latest report by the Centers for Disease Control and Prevention, 23,000 Americans die annually from drug-resistant infections.

Health officials believe the over-prescription of antibiotics used to fight respiratory illnesses contributes greatly to the development of these untreatable bacterial strains. But there may be a solution. Researchers at Duke, intent on stopping the spread of these “superbugs,” have designed a blood test to more quickly and accurately determine whether a patient has a viral or bacterial infection. The test detects specific genes activated when the immune system is under viral siege. (These same genes remain latent during a bacterial infection.) Given to 102 patients at Duke Hospital’s emergency room, the test was 90 percent accurate in diagnosing infections as viral or bacterial—and it took only twelve hours.

Geoffrey S. Ginsburg, coauthor of the study and director of Genomic Medicine in the Duke Institute for Genome Sciences & Policy, believes the test could help combat emerging diseases in addition to identifying common infections. “Current tests require knowledge of the pathogen to confirm infection because they are strain-specific,” he says. “But our test could be used right away when a new, unknown pathogen emerges.”