The BBC reports
that experts have discovered the first case of swine flu that is resistant to tamiflu, an antiviral drug being used to fight h1n1.
Roche Holding AG confirmed a patient with H1N1 influenza in Denmark showed resistance to the antiviral drug.
David Reddy, company executive, said it was not unexpected given that common seasonal flu could do the same.
The news comes as a nine-year-old girl has become the third to die in the UK with swine flu.
Virologist Professor John Oxford told the BBC, "I'm not surprised about this finding. The question is whether it is going to spread. We will soon know the answer."
The CDC has categorized swine flu as a Category 2 outbreak, with the possibility of 90,000 to 450,000 deaths in the U.S. There were 6,300 new cases in the U.S. last week.