“Dual mutant” flu strains with some resistance to antiviral drug found in U.S.

The CDC says at least two cases of so-called “dual mutant” flu strains have been detected in the United States. The strains have genetic changes that could impact the effectiveness of the main flu antiviral that hospitals rely on, commonly sold under the brand Tamiflu. Dr. William Schaffner, professor of infectious diseases at Vanderbilt University Medical Center, joined CBS News to discuss the virus.