Health officials say a record 40 percent of Americans got ordinary flu vaccinations last year, and fear of swine flu played a role.
The Centers for Disease Control and Prevention said the jump was most dramatic in children, but there was also a large jump in vaccinations of healthy younger adults.
For all ages, the highest seasonal flu vaccination rate previously was 33 percent.
Experts say more people got shots because they were worried about swine flu, which appeared last spring and was unusually dangerous to children and young adults. Seasonal vaccine was also available earlier than normal last year. And for the first time, vaccinations were recommended for all children.