Scientists have created a mouse that can catch a cold - raising hopes of new ways to treat serious respiratory conditions and asthma.
New treatments can now be tested in mice
It had been thought rhinoviruses, which cause most human colds and can trigger asthma attacks, could only affect higher primates.
The researchers hope their genetically modified mice will provide a valuable test-bed for potential new medications.
The study, led by London's Imperial College, appears in Nature Medicine.
Rhinoviruses are the major cause of acute attacks of chronic obstructive pulmonary disorder (COPD) - another name for chronic bronchitis and emphysema - which can be fatal.
Although they were discovered 50 years ago, the failure to find a way to infect small animals has proved to be a major stumbling block to developing new treatments.
As a result, there are curently no effective treatments.
Lead researcher Professor Sebastian Johnston said: "These mouse models should provide a major boost to research efforts to develop new treatments for the common cold, as well as for more potentially fatal illnesses such as acute attacks of asthma and of COPD."
Of the 100 known strains of the rhinovirus, 90% attack by latching on to a particular receptor molecule found on the surface of human cells.
The viruses cannot bind to the mouse version of the same receptor.
The latest research has succeeded in modifying the mouse receptor so it is more like the human version.
This meant the modified mice could be infected with the virus.
The researchers were also able to trigger asthma-like symptoms in the infected animals by exposing them to a protein found in egg white, which is known to provoke an allergic reaction in the lungs.
Sir Leszek Borysiewicz, chief executive of the Medical Research Council which funded the study, said: "This important and fundamental discovery will enable us to understand the effects rhinoviruses and common colds have on our health.
"It will open up new paths to finding treatments which have been delayed for many years and provides us with the opportunities for further breakthroughs in the future."
Leanne Male, of the charity Asthma UK, said: "Ninety per cent of people with asthma tell us that colds and flu trigger their asthma symptoms but as yet there is no specific treatment for virally induced asthma attacks and steroid treatments are only partially effective against them.
"We welcome this latest advancement as it will lead to a greater understanding of viral infections and their link with asthma and may help the development of a suitable treatment for virus-induced asthma attacks, thus greatly improving the lives of the 5.2 million people with the condition in the UK."