Scientists Come Closer to Unlocking Secrets of Common Cold

Oct. 25 -- FRIDAY, Oct. 24 (HealthDay News) -- It may not be the cure for the common cold, but it may set the stage for a cure.

Canadian and U.S. researchers have found that the human rhinovirus, long blamed for causing the common cold, doesn't actually cause those annoying sniffles, sneezes, and coughs.

Instead, the ubiquitous virus alters the activity of genes in the body, which then results in the misery that afflicts most people every year or so, according to a study in the first November issue of the American Journal of Respiratory and Critical Care Medicine.

"This is like the Wizard of Oz, showing what's going on behind the curtain, what the body is doing when there's a cold," said Dr. Ronald Kuppersmith, a clinical assistant professor of family and community medicine at Texas A&M Health Science Center College of Medicine, who was not involved with the research.

"This may provide opportunities to modify the body's response to the rhinovirus and provide opportunities for further research or possibly medication that would significantly reduce the symptoms and maybe even prevent infection in a much more targeted way," he added.

Human rhinovirus (HRV) causes some 30 percent to 50 percent of common colds and can also worsen more serious conditions, such as asthma.

"Everyone thinks the common cold is fairly innocuous, which it is. But if you have people with lower airway disease -- asthma, bronchitis, emphysema -- these viruses are now known to be very important triggers for people to have acute attacks and that can be life-threatening," said David Proud of the University of Calgary, the study's lead author and a professor of physiology and biophysics and Canada Research Chair in Inflammatory Airway Diseases.

For the study, 35 volunteers agreed to be injected either with HRV or a sham virus. Scientists took nasal epithelial scrapings both before and after infection.

A "microarray analysis" of DNA showed no genetic changes eight hours after infection. But, after two days, about 6,500 genes had been affected, either with heightened activity or dampened activity.