Gov. Bill Ritter asked for Colorado's share of antiviral drugs from a federal stockpile on Sunday as reports of swine flu cases mounted across the country. The request is a precaution, Ritter said, emphasizing that no cases of the deadly strain of influenza have been reported in Colorado. It's just a matter of time, even though cases in the United States have so far been "relatively mild," the state's chief medical officer said in a statement.