ATLANTA (AP) -- U.S. health officials say they won't need to change their response now that swine flu has been declared a pandemic.

Officials at the Centers for Disease Control and Prevention said Thursday that the government has already been treating the outbreak like a pandemic. Flu medicine has been sent out to states and money has been poured into a possible vaccination program.

Since the first cases of swine flu were reported in April, scientists have found the virus is not much worse than the seasonal flu.

The CDC's new chief, Dr. Thomas Frieden, says that should help keep people from overreacting to the pandemic declaration.

More than 13,000 Americans have gotten swine flu. So far, there have been at least 27 deaths.

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