Covid-19 cases dropped by almost 20% over the past week in the United States, marking the fifth-straight week of double-digit declines in case numbers. But the unvaccinated remain at significant risk, and fewer unvaccinated people report being willing to get a shot.

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Covid-19 cases drop as vaccination rates rise

Over the past week, the United States averaged about 24,000 new Covid-19 cases, a 20% drop from the previous week—continuing a trend of declining case rates each week since mid-April. In 38 states, Covid-19 cases dropped, while just four states saw case rates increase.

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Meanwhile, Covid-19 death rates over the past week dropped 9.1%, and hospitalization rates dropped by 10.5%.

The declining case rates come as the Biden administration announced Tuesday that half of American adults have completed all required doses of a Covid-19 vaccine.

"This is a major milestone in our country's vaccination efforts," Andy Slavitt, a White House senior adviser on Covid-19 response, said. "The number was 1% when we entered office on Jan. 20."

According to CDC, 50.6% of American adults have received all required doses of a Covid-19 vaccine, while 62% have received at least one shot. Meanwhile, 40% of the total U.S. population has received all required vaccine doses, while 49.9% have received at least one shot.

In 10 states, 70% of adults have received at least one shot, Slavitt said, adding in a later tweet that in an additional 10 states, at least 65% of adults are partially vaccinated. Meanwhile, more than half of all adults have received all required vaccine doses in 25 states.

A number of states have implemented unusual incentive programs to get more people vaccinated:

• Ohio entered vaccinated residents into a $1 million lottery called Ohio Vax-a-Million;
• California is offering gift cards and cash prizes to residents who get vaccinated;
• Minnesota Gov. Tim Walz (D) announced a campaign in which residents who get vaccinated will be eligible for a variety of prizes, such as state park passes and fishing licenses; and
• New York City announced it will provide buses at beaches and parks for people to "get vaccinated [and] hit the beach," according to Mayor Bill de Blasio (D).

Despite falling cases, the unvaccinated remain at risk

While Covid-19 cases and deaths have been declining nationwide, the unvaccinated population remains at significant risk, and polling suggests it may be difficult to persuade those who are not yet vaccinated to get a shot.

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"If you are vaccinated, you are protected, and you can enjoy your Memorial Day," CDC Director Rochelle Walensky said. "If you are not vaccinated, our guidance has not changed for you, you remain at risk of infection. You still need to mask and take other precautions."

Data reveals disparities in who has gotten vaccinated so far. For instance, as of May 1, the most recent date for which CDC has complete data, 28% of white Americans had received at least one dose of a Covid-19 vaccine, compared with just 19% of Hispanic and Black Americans.

At that time, there were 50 weekly Covid-19 cases per 100,000 among white Americans, compared to 69 per 100,000 among Hispanic Americans and 74 per 100,000 among Black Americans.

"The work ahead of us is going to be really challenging because, while the people who are fully vaccinated are well protected, we still have to keep on convincing individuals who are not yet vaccinated that they are not safe," Leana Wen, a CNN medical analyst, said. "The pandemic is not over for them."

Wen said the risk for unvaccinated people is approximately the same as it was during the January surge.

What might persuade the unvaccinated to get a shot?

But persuading unvaccinated Americans to get vaccinated may prove increasingly challenging. According to a recent poll from the Kaiser Family Foundation (KFF), just 4% of the unvaccinated said they plan to get vaccinated as soon as possible, compared with 9% in April.

Of those not ready to get vaccinated:

• 12% said they want to "wait and see" how the vaccine works first;
• 7% said they'd get vaccinated only if it was required by work, school, or other activities; and
• 13% said they would definitely not get vaccinated.

According to The Hill, 32% of those who are not yet vaccinated—including 44% of those who said they wanted to "wait and see"—said they'd be more likely to get vaccinated if FDA issued a full approval for the vaccines.

KFF's poll also suggested incentives may work, as 15% of the unvaccinated said they would be more likely to get a shot if their state government offered them $100. Meanwhile, 11% said free tickets to either a sporting event or concert would make them more inclined to get vaccinated.

"At this point, there's almost no low-hanging fruit, but there's a path toward a slow-but-steady increase in vaccination rates through improved access, information, persuasion, and incentives," KFF President and CEO Drew Altman said (Baker/Witherspoon, Axios, 5/27; Chappell, NPR, 5/25; Soucheray, CIDRAP News, 5/27; Kallingal, CNN, 5/28; Owens, Axios, 5/25; Coleman, The Hill, 5/28; Reed, "Vitals," Axios, 5/28; Holcombe, CNN, 5/27; Levin, New York Times, 5/25).