It was a threat that never materialized.
What did materialize were cases of a rare side effect thought to be linked to the shot. The unexpected development cut short the vaccination effort -- an unprecedented national campaign -- after 10 weeks.
The episode triggered an enduring public backlash against flu vaccination, embarrassed the federal government and cost the director of the U.S. Center for Disease Control, now known as the Centers for Disease Control and Prevention, his job.
Administrating a swine flu shot in 1976 - Los Angeles Times photo
The pandemic fears of the time and the resulting vaccine controversy may be fueling some of the public's -- and media's -- anxiety about the current outbreak, said health officials who recalled the previous event.
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