Klez-H tops monthly virus charts. Again
The old ones are still the worst
The infamous Klez-H was the most common virus circulating on the Internet this month. Again.
Monthly stats  from managed services firm MessageLabs show it blocked 366,393 copies of Klez-H over the last four weeks.
Virus infection rates are running at around one per 350 emails, compared to one in 30 infected emails at the heights of the Goner and Love Bug epidemics, MessageLabs reports.
Old favourites like Yaha variants (with 270,000 infection-bearing emails stopped) and SoBig (with 130,000 infection-bearing emails stopped) also feature prominently in the managed services firm's monthly stats.
By comparison newer menaces like LovGate.C , which drops a backdoor component on infected PCs, and Gibe-B , a virus that poses as Microsoft security updates and which went feral this week, barely get a look in.
A survey  by AV vendor Sophos, published earlier this week, highlights one of the reasons older viruses are still so common.
In a survey of 4,500 system administrators at companies of all sizes from all around the world, Sophos found that SMEs lacked diligence in updating AV signature files.
Nearly half of small to medium-sized businesses update their anti-virus software once a week or even less regularly, despite the deluge of virus targeting vulnerable boxes that assault networks every day. In contrast, 29 per cent of larger companies update their anti-virus software at least once a week. Still not brilliant but a fair bit better than SMEs, who in turn are doubtless more diligent than end users, manage.
So it becomes doubtful, baring a mass defection to alternative operating systems or apes taking over the earth, that we'll ever see the back of Klez-H. Depressing, isn't it? ®
Top ten viruses blocked by MessageLabs in February