Unfortunately, Omicron is far from done with us. More than 700,000 Americans are testing positive for COVID-19 every day, COVID hospitalizations in the United States are at a record high, and the variant is so contagious that an encounter with it can be postponed for only so long. The single best thing people can do to protect themselves is, yes, get vaccinated. And that includes booster shots.
The immunity boost of that third shot is something of a game changer: CDC data have shown that booster shots significantly ratchet up protection from Omicron hospitalization, compared with two vaccine doses. In some charts of COVID deaths and hospitalizations, the number of triple-jabbed patients is so low, you have to squint to find them in the graphs. And though it’s not clear how long this extra protection will last, what makes getting boosted now even more of a no-brainer is that the added protection starts to build in just a few days—far quicker than after the first shot—meaning that even this long into the Omicron wave, third shots can help stave off COVID’s worst outcomes, as well as immunologically arm us for whatever variant comes next.
And yet the rate of Americans who have received a booster shot is abysmally low. Although 87 percent of adults have received one vaccine dose, just 52 percent of eligible vaccinated adults are boosted—less than a third of the total adult population. One thing that could help is booster mandates—sticks over carrots. Mandates may be controversial, but they are effective. Even so, at least so far, we’ve seen astonishingly few companies or governments roll out booster mandates. Don’t expect many more: Last week, the Supreme Court batted down an effort by the Biden administration to mandate vaccines for large employers. Some companies, such as Starbucks, have responded by nixing the mandates they had voluntarily implemented.
So what about carrots? During the initial vaccine rollout, incentives were hot: Two dozen states were sweetening the immunization pot with million-dollar lotteries, a chance to drive your car on the Talladega Superspeedway, TikTok contests for $250 gift cards, tickets to baseball games, $100,000 scholarships, hunting and fishing licenses, a pontoon boat, a free beer at a local brewery, or just $100 to spend however you wanted. But even as booster shots could help lessen the burden of Omicron and future variants, governments have largely abandoned these ambitious incentive programs. I reached out to the 24 states that offered incentives last year, and of the 15 that responded, 13 aren’t offering financial incentives for boosters. Arkansas still hands out a $20 lottery ticket to anyone who gets a shot—including a booster—while New York is offering the unboosted a chance to win free ski passes.
This complacency around booster incentives is especially baffling because after a summer of lotteries and sweepstakes, we have a better sense of which programs show promise and which definitely don’t work. Incentive programs are never going to be the cohesive national strategy that gets us out of the pandemic. But they probably do still have a role to play: Unlike people who are staunchly opposed to vaccines, most of the unboosted are by definition not opposed to vaccines. Nudging them toward a third shot may be one of the lowest-hanging fruits in pandemic policy making.
Slipping someone a $100 bill might seem like a roundabout way for a country to induce its residents to accept a lifesaving vaccine, but last year officials were desperate to get shots into arms. Politicians of all stripes flocked to incentive programs because they appeal to both sides of the political spectrum. On the right, incentives align with free-market ideologies that place choice in the hands of individuals. On the left, incentives are alluring because they may alleviate equity issues by removing financial barriers for low-income populations.
Theoretically, incentives should work. Offering people cash to change health behaviors—whether to quit smoking or keep up with exercise—made a difference in previous studies. Cash might provide a fence-sitter justification to get vaccinated, or it might offer cover for someone whose desire for a vaccine goes against local social norms. And even though the COVID vaccines are free, they come with indirect costs, such as lost wages when taking time off from work to get a shot.
But theory is different from practice. “It was completely unprecedented for 24 states, more or less at the same time, to roll out these incentive programs,” says Kevin Volpp, the founding director of the Center for Health Incentives and Behavioral Economics at the University of Pennsylvania. In effect, it was a grand national experiment in whether financial incentives such as lotteries and cash guarantees work, so Volpp and his colleagues decided to put the numbers through the wringer. Despite the millions of dollars poured into these high-profile efforts, they found no difference in vaccination patterns between the 24 states with incentives and the 26 states without them.
Their study wasn’t an anomaly. Although the lotteries and cash giveaways generated much fanfare, and governors boasted of their effectiveness, a flurry of academic studies now suggests that most large-scale financial-incentive programs had minimal impact, or were total duds. It’s not clear why the incentive programs seemed to fail, but Mireille Jacobson and Tom Chang, two economists at the University of Southern California, have some suspicions.
Over the summer, they recruited 2,700 participants and randomly divided them into several groups—some were offered up to $50 in cash to get vaccinated, while others viewed public-health messages or received scheduling links that would make finding an appointment easier. The study itself took two months, but the analysis was basically ready in hours. “We could tell pretty quickly that there was no there there,” Chang told me. They found that for Donald Trump voters, the guaranteed $50 financial incentive actually decreased vaccination rates. “It’s not normal to pay someone to do something that’s good for them,” Chang said. If a vaccine is so good, the thinking goes, “then why do you have to pay people to take it?”
But that’s not to say we should give up on incentives altogether—especially now that the future of mandates seems shakier than ever. Even though statewide lotteries and beer giveaways proved to be gimmicky busts, there could still be a role for better-designed incentive programs, especially those that target specific populations. Unboosted Americans are disproportionately racial minorities, members of low-income families, and undocumented immigrants—the same populations that are most likely to be exposed to the virus and miss work because of COVID. For them, the chance to win millions in a lottery does nothing if they can’t physically get themselves to a vaccination clinic or take time off work. Booster incentives might be more successful if they were deployed in a way that acknowledges the complexity of human psychology, local social context, and structural barriers.
Sandrette Parker, a 47-year-old mother of three who lives in Henderson, North Carolina, told me that she faced these barriers. After a few months of hesitation, she finally decided that it was time to get her first shot. But there was a problem: She couldn’t get to a clinic. After losing her job, she said, “My choices were to pay rent, or pay my car payment.” Life without a car was tricky. “There’s no public transportation here, no city buses, and I don’t think I’ve ever seen a taxicab in this town,” she said. Parker finally found someone to take her family to the closest open vaccination site, some 50 miles away. A few months later, Parker said, she and her family tested positive for COVID. “Thankfully, we all had become fully vaccinated prior to catching COVID because I think it would have been worse.”
To address logistical issues like Parker’s, Charlene Wong, the chief health-policy officer for COVID-19 at the North Carolina Department of Health and Human Services, designed a clever incentive program during the late spring. Her team offered people in undervaccinated counties $25 cash cards to get vaccinated—but it also added a twist, what Wong calls a “social incentive.” Anyone who drove someone else to receive a first dose also received a $25 cash card. “Social incentives really leverage the fact that we have networks of folks around us to influence our behaviors,” Wong said. The design worked: Vaccination rates were decreasing nearly everywhere in the country by that time, and the program slowed the decline by half at clinics with incentives compared with neighboring clinics without incentives. With boosters, “those same barriers—transportation, lost wages, child care—they aren’t going to magically disappear,” Wong said.
What Wong’s study suggests is that simple quid pro quo financial incentives may not be sufficient to make vaccine access equitable. Julia Raifman, a public-health professor at Boston University, told me that “making vaccines easy to access—for example, a walk-in clinic, well advertised and nearby—and broad communications about who was at risk are likely more important than the financial incentives.” Community organizations around the country are racing to figure out what works. La Colaborativa, a Boston-area community organization, successfully increased vaccination rates in the low-income suburb of Chelsea to 92 percent by offering vaccination sign-ups at the same location people could pick up a box of free food or access social services. Our Healthy KC Eastside lifted vaccination rates in some of Kansas City, Missouri’s predominantly Black neighborhoods by 50 percent compared with the citywide average–by putting clinics in convenient locations and giving out $50 for first shots.
There’s been no systematic assessment of how effective these more targeted programs have been nationwide. But even without the sort of high-quality evidence we would want, there’s a moral argument that anyone who wants a life-saving vaccine should be able to access it–particularly those from communities that could gain the most from third shots. From a strictly economic perspective, pouring money into booster incentives is a bet, but perhaps one worth taking. No matter what happens with workplace mandates going forward, millions of people, including the unemployed and retirees, won’t be covered by them. Targeting these people will cost money, but so will leaving people less protected from COVID.
I asked Chang and Jacobson what they would say if the governor of California, for example, called them up tomorrow to inquire about a statewide incentive program for 2022. They both agreed that it would be pointless for first doses. “I’d say do it for boosters, though,” Chang said. Jacobson concurred. “I think there are a lot of people who are in this camp of Yeah, I’m gonna get a booster but I’m not in any rush,” she said. “And I would think those folks are probably pretty responsive” to financial incentives.
After all, the whole point of nudges is that you target someone who’s kind of indifferent, and for whom a small incentive slightly lowers the burden of time, effort, or actual financial cost. For incentives to work, you need a lot of people on the fence—which is exactly the place we’re in with boosters. And yet there’s no longer the spirit of experimentation that pervaded the initial vaccine rollout, or really, it seems, much of a plan at all. We now know that dumping money into big-ticket lotteries maybe isn’t the best idea. And sure, maybe incentives aren’t the answer at all. But compared with the economic and human costs of not getting Americans boosted, is the small probability of landing a free ski pass really the best we can do?