Public health authorities are reporting three cases of the H1N1 influenza in which the virus was resistant to the antiviral drug Tamiflu.
Until now, all tested strains of the novel H1N1 flu had been susceptible to Tamiflu. But the three cases of a drug resistant virus -- one each in Hong Kong, Denmark, and Japan -- suggest that resistance could arise.
What is most worrying some is that one of the cases of resistance occurred in a woman in Hong Kong who had not been treated with the drug. In the other two cases, the patients had been given the drug as a preventive measure.