Get vaccinated, get a prize: Will giveaways actually work?

For months, the biggest challenge facing the effort to vaccinate Americans against the coronavirus was a lack of supply to meet the sky-high demand from people eager to get the shot. That problem has reversed in recent weeks. Now the U.S. is dealing with a surplus of vaccine doses and not enough people willing to take them. The daily rate of vaccines administered has been cut in half since its peak in early April, raising concerns that the country may not be able to vaccinate enough people to reach herd immunity.

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