Firms were hit last year by an average of 113 virus infections per month for every 1,000 computers they own, according to a survey of end users by ICSA Labs.
The ICSA Labs' seventh annual computer virus prevalence survey show the threat viruses to businesses increased throughout 2001.
ICSA Labs, a division of TruSecure, polled 300 companies to for its latest survey, which concludes that the likelihood of firms falling victim to virus infection increased 15 per cent over the last two years.
Clean-up costs have also grown by a similar amount, even though firms are spending more on AV software and extending its use beyond PCs to email servers and perimeter devices.
Tis shows that AV software offers baseline protection only: filtering of suspicious email attachment types, user education and, crucially, virus blocking by ISPs needs also to be applied. And then there's Microsoft: it needs to make Windows and its Outlook email client less of a vector for virus infections.
The one bright spot in the survey is that a smaller percentage of companies (28 per cent) experienced a "virus disaster", where 25 or more PCs were hit by infection at the same time. Typically, these incidents less often led to server downtime than before, with two in three firms experiencing less than one hour or less downtime due to mass infection, compared to one in three experiencing downtime due to similar reasons last year.
It's also difficult to say how much such disasters cost firms as only 24 organisations responded to this question, and gave guesstimates of the total cost of a serious outbreak ranging from less than $100 to over $1 million.
The worst problem posed for firms arose from email-borne viruses with SirCam, the Love Bug, Home Page, FunLove and the Anna Kournikova worm emerging as the five bugs most bugs to infect corporate systems.
All the more reason for ISPs to offer services which block the problem at its source, by scanning email for viruses, we reckon. ®
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