This week marks the fifth consecutive week of widespread flu activity in Kentucky. Widespread activity is the highest level of flu infection.Typically flu activity reaches this level then falls after one or two weeks. Sometimes another peak comes later, after relatively low levels of flu infections.State epidemiologist Dr. Craig Humbaugh (HUM-bah) says one reason for the long-lasting peak is the flu vaccine itself, which didn’t protect against every type of Illness that developed this year.“This year’s flu season could be partly the result the fact that some unexpected flu strains are circulating nationwide," he says.Still, Humbaugh recommends that people continue to get immunized, especially those at risk of developing complications from the flu.