H3N2 strain is included in 2015 flu shot says MPH Program’s Schaffner
This year's flu shot is expected to be more effective than last season's vaccine. Last year was a pretty bad flu season because the H3N2 strain was the predominant strain, according to Dr. William Schaffner, a professor of preventive medicine who works at Vanderbilt University's Department of Medicine. Last year, when the virus mutated, the vaccine was only about 19% effective. But even some protection is better than no protection, Schaffner said.