Seasonal vaccine no help against swine flu

A U.S. Centers for Disease Control and Prevention official said Sunday afternoon that tests of the seasonal vaccine and the new virus show no cross-reaction, suggesting that people who got the vaccine have no added protection against the new bug.

It's possible that people who have been exposed to flu viruses every year — especially older people, with a greater exposure history — may have some natural immunity, the CDC official said in a call with reporters.