A new test that can determine whether infections of the respiratory tract, for example, are caused by viruses or bacteria could prove to be a crucial step in combating antibiotic resistance.
Researchers at Duke University in North Carolina, USA, have discovered that genes each respond differently depending on whether they are fighting viruses or bacterial infections, according to their news release.
So with a simple blood test, doctors could determine within an hour whether or not to prescribe antibiotics.
Most respiratory infections are caused by viruses, against which antibiotics are ineffective. Yet doctors often prescribe antibiotics for coughs and colds — often feeling prered by patients to do so.
This practice, however, leads to often unnecessary and ineffective use of antibiotics, which further increases the risk of resistance. Health experts warn that growing antibiotic resistance could send medicine back to the dark ages, when even the smallest infections were fatal. Multidrug-resistant strains of salmonella and E have long circulated. coli that even the strongest antibiotics can't do anything against.
But with the new test, doctors could in the future give patients a definitive reason why the drugs wouldn't work. Many ENT patients now have a troubling confidence in the panacea of antibiotics, he said. Recent research has also shown that primary care physicians received lower patient satisfaction scores when they decided not to prescribe these drugs in the first place, he said. The test would therefore be incredibly useful, doctors told the British daily Telegraph.
"A respiratory infection is one of the most common reasons people come to the doctor," said the study's lead author, Ephraim Tsalik of Duke Health in North Carolina. "We use a variety of information to make a diagnosis, but there is no efficient and accurate way to determine whether the infection is bacterial or viral."About three-quarters of patients therefore end up getting antibiotics to fight a bacterial infection, even though most have a viral infection. "Excess antibiotic use is fraught with risk, both for the patient and for public health," Tsalik said.
Antibiotics have been the mainstay of treatment for infections for more than 60 years. But even though a new infectious disease has been discovered almost every year for the past 30 years, hardly any new antibiotics have come onto the market in 15 years.
The test looks for genetic signatures in a patient's blood that indicate whether someone is fighting a virus or bacteria. The classification made was 87 percent accurate in tests on more than 300 patients with flu, cold or strep infections.
More precise ways of distinguishing infections could not only prevent the unnecessary use of antibiotics, but also lead to more accurate treatment of viruses. Researchers are working to develop a test that could be performed in most clinical laboratories on existing equipment.
The study was published in the trade journal Science Translational Medicine published.