Half of the security breaches affecting British businesses were the result of computer viruses, a survey by the Department of Trade and Industry has revealed. Infections can take certain parts of (or entire) systems down for a day or more, with the longest infection taking fifty days to completely eradicate.
The good news revealed by the survey was that the number of firms caught out by viruses had dropped by almost one-third since the last time the study was done in 2004.

This reduced infection rate was put down to the fact that most businesses now use anti-virus software to clean up e-mail traffic before it reaches in-boxes.

Chris Potter, a partner at PricewaterhouseCoopers and one of the report's authors, said firms had got much better at keeping their anti-virus software up to date and patching vulnerable systems.

But, he said, it was hard won experience. "They know how much this can hurt if they get caught out."
[BBC News]