I have had an iMac since August 2012 and have never scanned it, do you need to scan the iMac for bugs or is it not needed?
You don't have to do anything. Just keep OS X updated in order to get fixed existing bugs and that's all. Apart from that, you don't have to worry about viruses. See > http://www.thesafemac.com/mmg
You are welcome
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