AS many as 300 different computer viruses spread their way across the global networks each month, according to estimates by national accountancy group Hacker Young. Currently the most serious and debilitating virus is an official code red virus called NIMBA.

"NIMBA is causing havoc for business as it sprawls its way around the world," said Nick Hay from Hacker Young's Manchester office.

"It infects computers by three points of attack -- firstly by way of an e-mail attachment.

"Secondly upon contact with an infected website and thirdly via the server, by clogging up opening ports."

Hacker Young is extending its expert prevention service to outside businesses and is offering a complete security check to ensure that systems are healthy and virus free for 12 months.