It was always a misconception that a Mac was immune to attacks, it was mainly due to the relatively low numbers not making it worth while for the hacker.
It's still a much better platform from a virus point of view than Windows by a million miles. The chances of you getting infected on Windows remain substantially higher and will remain so for the foreseeable future.
Simple fact of the matter is that you do not need antivirus on a mac if you follow basic maintenance steps and common sense when on the internet. I have checked all my macs for the presence of that virus, on none of which I run an AV, and have not found it.
So can we please take the journalistic hype with a pinch of salt. Yes there is something to be aware of, and yes you should exercise caution (whether using a mac or any other computer). But the fact of the matter is that the underlying security posture of the mac platform remains broadly unchanged, and so the world is not going to end tomorrow !