This year’s flu vaccine might not offer much protection against the strains of the influenza virus currently circulating, according to a new study. Each year, the flu vaccine is created to protect against what are expected to be the dominant strains of the virus. This year, the flu vaccine was designed to protect against four specific strains: H3N2, H1N1, and two strains of the influenza B. But researchers at the University of Pennsylvania believe that the prevalent version of H3N2 has mutated to avoid the antibodies the vaccine helps our bodies make. It is important to get the flu vaccine, as it can still protect you from serious illness even if you are exposed to a virus strain the vaccine doesn’t completely prevent.