How Do You Distinguish Flu from Colds, Pneumonia?
You're ailing. You have respiratory symptoms of all sorts from a runny nose to coughing fits. Is it the flu? a cold? Or for real pessimists -- pneumonia? How do you know? How does your doctor decide?
It's a bit of a sticky dilemma. Sometimes a physician's guess is as good as your own; but when optimal treatment depends on an accurate diagnosis, the more you know the better you will be in the long run.
Today, the best diagnosis comes from laboratory tests that can take days to process. By the time the results are in, however, the patient could have been on treatment for the wrong thing. And pulling in antibiotics for the wrong reason just plain can be dangerous to long-term health.
But the testing may change dramatically in the near future. Researchers at Duke University in Durham, N.C., are studying genomic "signatures" in blood that appears to be able to identify people who have been exposed to common upper respiratory viruses like the cold or flu even before symptoms develop.
They looked specifically at 60 healthy volunteers who were infected with a live cold virus, respiratory syncytial virus or influenza A virus and identified changes in 30 genes that are activated as the body responds to infection.
The genomic signature is strong enough to reveal whether the infection is viral or bacterial and can identify who has a viral infection and who does not, according to researchers.
The body's immune system responds quickly and in a specific way when exposed to a virus as opposed to bacteria, noted lead author Aimee Zaas, MD, an infectious disease specialist at Duke.
"A detailed reading of that response, using gene expression data, revels what type of pathogen the person is reacting to," Zaas explained in a university press release.
The study appeared in August in the publication Cell Host and Microbe and could lead to changes in the ways doctors care for people with upper respiratory infections.
Bacteria can be treated with limited number of antibiotics; virus with chicken soup, lots of bed rest and fluids. But the two methods are not interchangeable. Pneumonia falls into two categories as either bacterial or viral so a good diagnosis is greatly beneficial for the treatment.
Time frames for reading test results from signature blood samples were not provided in early releases.