This Season's Flu Virus Is Resistant to 2 Standard Drugs

Doctors should stop prescribing two standard antiviral drugs to treat or prevent this season's influenza because the predominant strain has quickly become resistant to them, federal health officials said Saturday.

The standard drugs are amantadine and rimantadine.

Instead, the Centers for Disease Control and Prevention recommended that doctors prescribe two newer antiviral drugs, oseltamivir (Tamiflu) and zanamivir (Relenza), and said ample supplies were available.

The new findings concern only the strain of influenza causing regular seasonal influenza, and not avian influenza or pandemic influenza, said the centers' director, Dr. Julie L. Gerberding.

She said 91 percent of the human influenza A (H3N2) virus samples isolated in her agency's laboratories this flu season were resistant to both amantadine and rimantadine. A (H3N2) is this season's dominant strain. The agency's influenza surveillance program studies samples from state health departments.

Courtesy of The New York Times