Health Officials: Type Of H1N1 Resistant To Tamiflu

Health officials said Friday the four cases were reported at Duke University Medical Center in Durham over the past six weeks.

Tamiflu is one of two medicines that help against the H1N1 virus. Health officials have been closely watching for signs that the virus is mutating, making the drugs ineffective.

About 52 resistant cases have been reported in the world since April, including 15 in the U.S. so far. Officials with the U.S. Centers for Disease Control and Prevention say almost all the U.S. cases have been isolated.

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