A new device may speed
diagnosis of respiratory viruses
Current tests take too long to diagnose respiratory viruses. And when a diagnosis is finally made, anti-virals don't usually work, because the virus has already overwhelmed the body. A new device especially made for respiratory syncytial virus (RSV)--a leading cause of respiratory infections in infants and young children--could be packaged in a disposable device about the size of a ballpoint pen. It would detect a virus in a few minutes via a gold wire and fluorescence scanner, Vanderbilt University researchers say.
A Vanderbilt chemist and a biomedical engineer have teamed up to develop this respiratory virus detector, which is simple enough to be performed in a pediatrician's office.
Writing in The Analyst--a journal published by the Royal Society of Chemistry--the developers report that their technique, which uses DNA hairpins attached to gold filaments, can detect the presence of respiratory virus at substantially lower levels than the standard laboratory assay.
"We hope that our research will help us break out of the catch-22 that is holding back major advances in the treatment of respiratory viruses," says associate professor of Chemistry David Wright, who is working with professor of Biomedical Engineering Frederick "Rick" Haselton on the new detection method.
According to the chemist, major pharmaceutical companies are not investing in the development of antiviral drugs for RSV and the other major respiratory viruses because there is no way to detect the infections early enough for the drugs to work effectively without harmful side-effects.
"There are antiviral compounds out there--we have discovered some of them in my lab--that would work if we could detect the virus early enough," he says.
By contrast, "our system could easily be packaged in a disposable device about the size of a ballpoint pen," says Haselton.
To perform a test, all that would be required is to pull off a cap that would expose a length of gold wire, dip the wire in the sample, pull the wire through the device and put the exposed wire into a fluorescence scanner. If it lights up, then the virus is present.
Currently, there are several standard tests for RSV including culturing the virus, polymerase chain reaction (PCR) and the enzyme-linked immunosorbent assay (ELISA). To have any of these tests done, doctors must send a mucous sample from a patient to a special laboratory. When combined with delivery times, backlogs and other delays, it frequently takes a day or more to get the results.
Source: Vanderbilt University