The ESET enterprise (http://www.eset.eu) posted a news about a worm going around that destroy the MBR (Master Boot Record) of affected computers. They also highlighted that the data restoration is more complicated than usual.
As part of security best practice, we would like to remember you to verify that your anti-virus signatures are updated daily.
Article: http://www.eset.eu/press-computer-worldwide-targetted-by-MBR-Worm