"It's the best vaccine we have, but there are cases of influenza that occur despite immunization, " Schaffner said.

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"It's the best vaccine we have, but there are cases of influenza that occur despite immunization, " Schaffner said on "CNN Newsroom" Thursday morning.

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"It was debated by the CDC Advisory Committee on Immunization Practices for many years, and the indication for the use of influenza vaccine for an increasing number of groups on a piecemeal basis didn't make sense, " Schaffner said.

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I'm glad you are thinking about ways to protect yourself from the flu (influenza) since the flu season can continue as late as May of each year, and immunization can prevent or lessen the severity of a case of the flu.

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