I have been using long before it became popular. That lack of popularity meant that virus author saw little value in writing for the Mac platform. Once, several years ago during the spyware epidemic, a work colleague of mine mentioned that he was switching to the Mac platform because he was sick of viruses and spyware. At that moment I knew it wouldn’t be long before Mac were a target of malware authors.
Now that the market share for Macs has risen the platform is more likely to be under attack — which was foreseeable. Don’t forget to take precautions and install antivirus software. The security firm Sophos provides free Mac antivirus software.