Scientists are boldly predicting we may soon have to stop complaining that if we can put a man on the moon, why can't we cure the common cold?

Researchers have cracked the genetic code for all 99 known strains of the human rhinovirus, the virus that accounts for the majority of human cold infections.

The work, published this week in the journal Science, could lead to the first effective treatments for the common cold within five years, researchers say.

But they also found something entirely unexpected: The viruses have an uncanny ability to swap genes and make completely new strains, something once thought impossible.

As well, more than one virus can infect people at a time.

"That's why we'll never have a vaccine for the common cold," lead author Ann Palmenberg, professor of biochemistry and chair of the Institute for Molecular Virology at the University of Wisconsin-Madison, said in announcing her team's work.

"Nature is very efficient at putting different kinds of paint on the viruses."

This genetic intermixing, called recombination, might also lead to the emergence of a new strain, a highly infectious bug that causes more severe respiratory trouble than garden-variety cold bugs, warns senior author Dr. Stephen Liggett, professor of medicine and physiology at the University of Maryland School of Medicine.

The work to create the codebook for what's inside cold viruses lays the groundwork for better drug design, Liggett said in an interview.

It won't be as simple as "one drug fits all", he says, but rather different anti-virals targeted at specific gene regions.

"What we're trying to do is immediately attenuate it. I don't think we're going to have the situation where you're taking a pill every day for your whole life to keep from getting the common cold," Liggett says, "but I think it's going to be better than just treating the symptoms.

"You get infected. You take a pill. You'll have a couple of bad days, but it won't be a week, like some of these can take you down."

University of Ottawa virologist Earl Brown says the work is important because it provides the first detailed look "at the largest group of viruses that cause the commonest type of infections in humans."

Young children contract around six colds per year, adults, two.

Sequencing the cold virus is one thing, Brown says. The harder problem will be figuring out how the genes work, how the viruses mutate and which ones matter most. With so many different strains, "it will make it hard to get an effective therapy hit against any one of them."

More than half of asthma flare-ups are caused by rhinovirus infection. It's the No. 1 reason children visit a pediatrician because of an ear infection. Studies have shown that the risk of a child developing asthma later in life is 10-fold higher if they have a serious rhinovirus infection before age two.

"If you add up the cost of inappropriate antibiotics and some of the over-the-counter medicines people use to try to help with symptoms, we calculated somewhere between $60 billion and $100 billion is spent every year (in the U.S.) on the common cold, so why not take it seriously," Liggett says.

The researchers worked on a frozen collection of rhinoviruses taken from patients over a period spanning two decades.

From that they built a kind of family tree "that tells you who is related to who, who's closely related and who's distantly related," Liggett says. "The distantly related ones turn out to be the ones not responsive to the same drug."

Of the 99 strains they sequenced, 23 looked as if they were the result of a recombination between two others. Some viruses mutate to escape infection-fighting antibodies produced by a person's immune system.

"Although the rhinoviruses are pretty tame they come from a pretty nasty family that has closely related viruses that infect the nervous system and heart," such as polio and cardiovascular viruses, Brown says.