It sounds like the bug is jumping to memory at start-up, nothing new. It's really easy to deal with, if you have access to another computer and a external hard drive enclosure. Take drive out, put in enclosure, plug into another computer, run anti-virus, malware program. I like Avast for AV, spybot for malware.

Mac or PC it's just a program, it can't be bad, or really do anything on it's own. Sounds like you were running inferior protection. As I said Avast has worked great for me, as has Spybot, and Ad-aware.