It is a common mistake to think that if you have the latest antivirus software then you are protected from the latest viruses.
Any virus needs to be run in order to infect or damage the computer.
A good anti-virus program that is updated every few month can protect your computer almost perfectly. Don't Download, Copy, Execute or Insert any program or floppy from somewhere suspicious. AntiVirus software is a widely used product which you should install and update regularly. As long as you did not run it, nothing can happen. We are not aware of mail readers which can decode and execute messages automatically, but you should always check in your mail reader setup that no such switch is enabled.