Flu shot forecast

While last year's flu vaccine was mostly ineffective, the U.S. Centers for Disease Control and Prevention says this year's version should work better.

Last flu season the CDC was taken off guard as the dominant flu strain circulating in the U.S. mutated after the vaccine was formulated, according to NPR.org. While flu vaccines typically are effective 50 percent to 60 percent of the time, last year's vaccine was effective for only 13 percent of people who got inoculated.

But as flu season ramps up—it can last from October to May—the most common strains currently making nationwide rounds match this year's vaccine, the CDC says. Director Thomas Friedland encouraged people to get vaccinated because “that's the best way to protect yourself, your family and your community against flu.”