Worms made up more than 70 per cent of malware in February, according to antivirus specialists.

MyDoom.A and Sober C topped the infections charts for the month, with most of the Bagel and Netsky variants arriving too late in the day to register in the top 10.

"Once again, worms remain the main threat we are facing," said David Kopp, head of TrendLabs in Europe, the Middle East and Africa.

"There is still a significant lack of awareness regarding current internet security threats.

"Companies can significantly reduce the risk of becoming infected by putting into place some kind of aggressive security awareness campaign."

While Sober C and MyDoom.A dominate the charts, Lovegate and its variants are also still widespread. All these viruses arrive in infected attachments and must be activated by the target.

"You cannot excuse virus writers, but we could do more ourselves," said Professor Neil Barrett, technical director at Information Risk Management.

"All of the current big name viruses rely on the target being curious enough to open the attachment. If in doubt, don't."