UK small businesses are worrying complacent over the threat of sophisticated viruses, despite the financial losses caused by such attacks, a new report has claimed.

A study by ServGate Technologies found that a third of companies took no action at all after a ‘blended’ attack – a network problem that seeks to maximise damage by combining methods, such as viruses and worms.

This lack of action is despite the fact that blended attacks cause an average of 11 hours computer ‘downtime’.

The viruses cost 44 per cent of companies more than £1,000, with seven per cent claiming the attacks cost them as much as £10,000.

Worryingly, 23 per cent of those surveyed by ServGate didn’t know whether they had been hit by a blended attack, while just under half admitted they didn’t know how to deal with the sophisticated virus.

Computer viruses and worms have proved to be a regular headache for small businesses, who often do not have the resources to protect themselves or the ability to retrieve lost or damaged information.

Outbreaks so as the SoBig virus earlier this year have forced many firms out of business due to lost data.

Acthison Frazer, of ServGate, said that businesses need to wake up to the very real danger blended threats pose.

“With an estimated 3.8 million businesses in the UK, a severe blended attack would be disastrous for the UK economy.

“With increasing sophistication of attacks combining viruses, worms and malicious codes, companies lack knowledge in how best to combat this,” he said.