The government has had a £1m jab against viruses to bolster its departments' email security.
The virus protection deal with UK-owned MessageLabs is intended to ward off mass mailing viruses such as Lovebug, SirCam and Goner by identifying and stopping them before they reach the government's network boundaries.
The Government Secure Internet (GSI), which provides the secure network infrastructure for all government departments, will boost its antivirus protection with the SkyScan AV managed service.
MessageLab partner Cable and Wireless, which provides the GSI infrastructure, will deliver the antivirus service.
Bob Evans, director of Information Assurance and Resilience at the Office of the e-Envoy, said: "Effective information assurance needs a robust, effective antivirus service."
He added that the government must comply with former Civil Service head Sir Richard Wilson's comment that information assurance is "right in the centre of the playing field, and the importance for the government is to have its own house in order".
The software scans emails at the internet level before passing them on their final destination. MessageLabs said it uses patented artificial intelligence to identify new virus outbreaks without the need for signatures.
While testing the service last year, MessageLabs said it deflected 21,167 copies of Goner directed at government email over the first three days of the outbreak.
Ben White, chief executive and joint founder of MessageLabs, said: "Attack from email viruses is a clear and present danger for the government, and the consequences could be very serious indeed.
"For example, the Goner virus deleted security software and other executable files from networks, while SirCam emailed private documents around the globe."
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