Just as you back up frequently, virus check frequently. Don't back up your viruses. Scan first to see if you've been hit. If you backup your virus-attacked software, you'll only get hit again if you ever restore the infected software. Scan first, then back up.
Mass media start panics at the slightest hint of trouble in the name of news.
Doing so keeps their audience. You don't have to fall for it. The last Michelangelo virus scare was little more than that - a scare, not an epidemic. Protecting the flow of new executable files into your system will reduce the likelihood you'll get infected. Vigilance when you acquire new software from any source will reduce the harm any potential infection could deliver.