Lai suspects that this may help explain how the virus is able to escape the immune system's attack and so can develop into a chronic infection in many patients. It may also explain how the virus damages the liver and causes hepatitis. He hopes his research will lead to new ways to treat people already infected with hepatitis C, so that doctors can stop the virus before it causes serious liver disease. After all these years, studying viruses' shifty ways continues to leave Lai with a sense of amazement. Part of this comes from the ability of viruses to shuffle genes with as much deft as some genetic engineers.
Viruses can pick up pieces of cellular genes or incorporate their genes into the cell's genome.
That means that evolution occurs all the time in viruses.