But even if it hasn t touched you and yours, it s quite sure to, eventually.
Viruses insert their genetic material into a cell and make it into a virus factory.
In the end, this kills the infected cell and it s that cell death that causes disease. The most important defense against viruses is the immune system. But there are particularly clever viruses, called RNA viruses, which can tap dance around the human immune system. They change their identities quicker than a con man. By the time the immune system gets a line on them, they ve turned into something else.