10% spyware


Psssst…  Buy a Mac!

But in all seriousness, does owning a Mac prevent against catching PC AIDS, such as this?

Yes, for the most part you are immune to these types of spyware infections.  Macs are based on Unix which is a very sturdy OS; Unix is immune to most viruses, spyware.  However, make sure you keep your Mac patched with the latest security updates.  Linux is also immune to Windows viruses.
In theory there are Mac and Linux viruses out there, but, not much to worry about.