A better booster campaign
Here we go again. Pandemic fatigue coupled with the most contagious Omicron subvariants yet, BQ.1.1 and XBB, are driving yet another viral surge across the globe. Pair this with waning immunity and suboptimal booster uptake among the vulnerable, and the U.S. may see what’s happening in Germany right now.
Why is booster uptake suboptimal? Throughout the pandemic we have leveraged “bench science”—a field that deals with things that can be observed and measured explicitly in a lab, such as immunology and virology. This was crucial as it got us innovative, novel COVID-19 vaccines in record time. However, vaccines in vials are not useful; vaccines have to get into arms. This is where we have desperately missed the mark in our pandemic response as we have not leveraged “social science”— a field that studies people and behaviors, which can be more difficult to predict.
I partnered with two social scientists, Benjamin Rosenberg, Ph.D., and Jason Siegel, Ph.D. who study psychology and how it impacts healthy choices. Their efforts were recently showcased in the New York Times on how Marin County—a wealthy Bay Area county—had the lowest rates of child vaccination more than a decade ago but now has one of the nation’s highest COVID-19 vaccination rates.
Social science perspective
Several years ago, Dr. Siegel was doing research on how to persuade people to become organ donors. This work resulted in something called the IIFF Model—a framework that maximizes the likelihood that people will act on their favorable attitudes—bridging the gap between feeling good about something and actually doing it.
Their work describes an orientation called passive positive. Drs. Rosenberg and Siegel thought that, given similarities, this model could be applied to better understand the low booster shot uptake.
In COVID-19, passive positives are people who are not motivated to find out if they are eligible for another booster, are actively trying not to think about COVID-19 or the booster, are not willing to exert energy to find out where they can get another booster shot, and are likely ambivalent about receiving the shot (e.g., may have positive attitudes about the protection it gives and negative attitudes about the immediate side effects).
All of this paints a relatively counterintuitive picture, as folks who have received two, three, or four COVID-19 shots are likely to hold relatively positive attitudes toward the vaccine—they were, after all, willing to get the primary series—but have yet to get the fall booster. The IIFF Model could offer some guidance that should bump up booster uptake:
Immediate and complete booster opportunity: If people lack motivation to get a booster, they will be less likely to exert effort to receive one. Moreover, even if someone becomes motivated to get a booster, that motivation is likely to be short-lived. As such, it is critical to have a booster shot immediately available the instant a person becomes motivated to get the shot. Doctors’ offices and pharmacies seem like easy and logical places to do this.
Information about eligibility for a booster: An oft-cited barrier to receiving a booster shot seems to be a relic from many months ago when it was unclear who, exactly, could get boosted. Now, though, nearly everyone who has received two shots is eligible for a fall booster—whether they know it or not. Even though this information is available on numerous websites, passive positives are not inclined to search for additional information due to a lack of motivation. As such, this information must be proactively presented to passive positives (e.g., via doctors, nurses, or pharmacists, as well as public health messaging).
Focused engagement at the time of the booster opportunity: People are exhausted from more than two years of COVID-19; they likely now turn away rather than toward information about it. As such, we need to take steps to make sure people actively process information about the benefits of booster shots. Behavioral supports must be implemented (e.g., doctors and pharmacists telling those who have received two shots that they can receive another one—ideally right then) to ensure that passive positives will engage with the information provided about the booster and that they are aware of the immediate opportunity to get one.
Favorable activation of booster attitudes at the time of booster opportunity: Although people who have received two COVID-19 shots but not a third likely feel positively about the vaccination, it is unlikely that their attitudes are entirely positive. That is, this group probably also harbors some negative feelings about the vaccines—perhaps rather than thinking about the lives that vaccines have saved, they think about the people who have had breakthrough cases of COVID despite being boosted. At the time a booster is offered, then, the practitioner should purposely encourage patients to focus on the positives of being boosted (e.g., increased short- and long-term protection).
Putting it all together, imagine a scene in a CVS pharmacy: Any time a medication is given to a customer, the pharmacist can ask about vaccination status (or check the patient’s records). If the patient is not boosted, the pharmacist can let them know they are eligible to receive a booster, that they can receive one right now, and describe the benefits. Ideally, the pharmacy could have posters advocating the benefits of booster shots so the topic is salient even before the pharmacist breaches the topic. This approach can work because all four elements of the model are simultaneously present. However, if even one aspect of the model is missing, the likelihood of success drops dramatically. Pharmacies are currently understaffed, overwhelmed, and burnt out. Getting vaccines into arms has to be an investment and public-private partnership, just like we did to get vaccines into vials.
Another great, real world example of this model is a success story in increasing COVID-19 vaccination rates among children in Boston.
There is no one foolproof strategy to increasing booster uptake. At this point in the pandemic, a promising approach is aiming to persuade passive positives—people with favorable booster attitudes but little motivation to get one. This is less about “bench science” and more about “social science” —meeting people where they are. It will move mountains.
Love, YLE, Dr. Siegel and Dr. Rosenberg
Dr. Siegel is a professor of social psychology at Claremont Graduate University and director of the Depression and Persuasion Research Lab. Dr. Rosenberg is an assistant professor of psychology at Dominican University of California and director of the Health and Motivation Lab.
“Your Local Epidemiologist (YLE)” is written by Dr. Katelyn Jetelina, MPH PhD—an epidemiologist, data scientist, wife, and mom of two little girls. During the day she works at a nonpartisan health policy think tank, and at night she writes this newsletter. Her main goal is to “translate” the ever-evolving public health science so that people will be well equipped to make evidence-based decisions. This newsletter is free thanks to the generous support of fellow YLE community members. To support this effort, subscribe below: