A week ago security experts at Sophos were recommending home users should switch to Mac, now Symantec has published a weblog claiming that "Mac OS X security threats are almost completely lost in the shadows cast by the rocky security mountains of other platforms."

The blog is written in response to "tired conspiracy theories" that emerge "whenever security and Mac OS X are mentioned in the same breath."

It claims: "There are no file-infecting viruses that can infect Mac OS X." Noting that those well publicised cases of security threats to the Mac, such as OSX.Leap.A (also known as the Oompa Loompa) was a worm, and not a file-infecting virus.

Sophos emphasises the over use of the term 'virus' as a generic reference to any malicious code. "Here at Symantec we tend to use more appropriate blanket terms like security threat and malicious code."

However, the company recognises that a security threat does exist: "Please remember that Mac OS X has been tested by worms, Trojan horses, rootkits, and other various security vulnerabilities," it says, adding: "No operating system is without imperfections, and no computer connected to the internet will ever be 100 per cent immune from attack."