Influenza vaccine via "jet injector?" FDA says no

(CBS) The FDA shot down the use of "jet injectors" to deliver influenza vaccines, saying in a written statement that "all vaccines, including influenza, must be administered in accordance with their labeling."

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The sharply worded warning came after the agency received inquiries about the use of the needle-free injectors, Medpage Today reported.

The agency said there were no data to show the safety or effectiveness of flu shots delivered by injectors, which instead of hypodermic needles use a thin, high-pressure jet of liquid to penetrate the skin.

Currently, flu vaccines are approved only for administration via needle or a nasal mist spray.

What about people who have received the flu shot via a jet injector - do they need to be revaccinated?

"We're still looking into the issue and unfortunately at this very moment, we can't answer that question," CDC spokesman Tom Skinner told the Columbus Dispatch. "But we hope to be able to very, very soon."