When you say,"PCs" you mean computers with MS windows operating systems?
If you run windows on your mac through boot camp that designated part of your Mac is open to the same viruses as PCs that run MS windows.
Well as the question posed in your title is totally nonsensical (both the statements your question is comparing make no sense), the answer isn't even "yes" or "no". It might as well be 'teapot'.
Is there some context you've taken this from that I'm not recognising which would help explain why you're asking this question?
Ever tried charging a Nokia phone with a Samsung charger? Doesn't work. Same with program compatibility on OS X and Windows. You cannot run a OS X program on Windows. You cannot run a Windows program on OS X.
The same applies for 'viruses', even though there are no viruses for OS X.