You can safely ignore viruses on the Mac. If there EVER is a real virus in the wild that affects Macs, it will make the evening newscasts it will be so publicized. You won't miss the news. At that point you can start to think about virus protection. Until that happens, no need to worry and waste time over a non-existent issue.
This isn't smugness, it's reality. If that changes, my attitude will change, but it hasn't yet.
As for that jailbreaking method where you go to a site and slide to unlock, Apple already fixed that in iOS. It was a bug, it's fixed, it's over. Just watch the news and you'll know what to avoid. Keep your software updated and any new holes will get plugged.
What if you do jailbreak your iPad? Then you need to worry.