Six out of 10 companies claim they will give up email if the threat posed by viruses, spam and other unwanted content is not contained and a viable alternative emerges.

Responding to an email security survey carried out by MessageLabs a further 40 per cent said they feel 'worried' by the current email security threat to their business, with only 29 per cent feeling 'optimistic'.

The survey shows that few (15 per cent) think email will remain the same application over the next decade, while two thirds think it will merge with other messaging applications, such as wireless and instant messaging. But only 14 per cent of respondents think it will become completely obsolete.

Over 20 per cent of firms responding to the research indicated that online fraud such as phishing and identity theft will be the greatest threat. Viruses achieved a similar rating (21 per cent).

The leakage of confidential or sensitive information was rated by 18 per cent as the main issue, with 15 per cent stating that it would be the potential for industrial espionage.

The survey reveals continued concern over levels of spam, with over 40 per cent of respondents predicting that levels of junk email will more than double over the next 10 years, and a further 24 per cent expecting it to rise by more than 50 per cent. Only four per cent think it will be non-existent.

Mark Sunner, chief technology officer at MessageLabs, said in a statement: "These results clearly show that concern about email security continues to run high, to the extent that if the situation does not improve the status of email will be under threat.

"The convergence of the various email attack methods has led to a more damaging and complex breed of email security threat, meaning that everyone's favourite 'killer app' is also capable of mortal damage to the business."