The U.S. continues to dominate as the main source of the world's viruses, producing 15.9 percent of all viruses. It is followed closely by Brazil, which produces 14.5 percent (similar levels to last month's 14.1 percent).

You can see more about virus trends from the Microsoft Security Intelligence Report:
http://www.microsoft.com/security/portal/Threat/SIR.aspx

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