A leading technology writer has issued stark warning to Mac users to take an active stand to protect themselves against viruses and malware.

BBC's Bill Thompson warns that despite the relative scarcity of Mac-affecting Internet-borne threats, there is no reason to be complacent.

Thompson thinks Mac users are taking security for granted, an approach he calls "too smug".

"Mac users demonstrate an indefensible smugness when it comes to the dangers of having their systems compromised by malicious software and opened up to exploitation by others," he writes.

He points to Apple's regular security patches as evidence that harmful forces are at work to create malware for Macs. While it's had to install, it isn't impossible - particularly as the Unix the Mac OS is built on has its own security problems.

"Any Mac user who believes they are totally safe is being reckless with their files and personal information. What's worse, they are also being reckless with mine," he writes.

Leaving Macs unprotected now leaves them vulnerable to an effectively-written security threat in future, he warns.

"It's time Mac users started behaving a bit more responsibly," Thompson concludes.