Combatting Vaccine Hesitancy

Building Confidence in Vaccines and Reducing Vaccine Hesitancy: How Vaccine Messaging Helps to Improve Vaccine Uptake in Hesitant Portions of the Population.



Maciej Boni

Associate Professor, Department of Biology; Center for Infectious Disease Dynamics
JPD 2021 cropped

James Price Dillard

Distinguished Professor
Communication Arts and Sciences
Erina MacGeorge

Erina (MacGeorge) Farrell

Professor, Communication Arts and Sciences
Lijiang (L.J.) Shen

Lijiang (L.J.) Shen

Professor, Communication Arts and Sciences

Background Info

People base their vaccination decisions on a variety of factors, including the perceived risk of contracting the disease, trust in the vaccine safety and the health care system that produced it, degree of protection produced by the vaccine, and the personal costs of obtaining it. Following these judgments, some individuals get vaccinated, some do not, and a large portion of the population remains ambivalent. This project asks how vaccine messaging help to improve vaccine uptake in hesitant portions of the population.


Vaccine hesitancy is the phrase used to describe individuals who refuse vaccines or delay vaccination despite availability, effectiveness, and safety. The number of people who are vaccine hesitant varies across regions, communities, countries, and continents, as well as diseases. With the introduction of new vaccines, such as COVID-19, hesitancy is often high due to unfamiliarity and uncertainty.

Health messaging is an important means of building confidence in vaccines and reducing vaccine hesitancy. Vaccine-promoting messages usually focus effectiveness and safety. For example, messages may emphasize the degree to which vaccination benefits individuals or others, and how un-vaccinated individuals are at higher risk of infection, hospitalization and death, and how unvaccinated persons may harm others by contributing to transmission of the disease. The CDC and other health authorities have observed that a one-size-fits-all strategy for pro-vaccine communication often backfires. What is needed instead is the development of messages that are tailored to different groups based on their needs, wants, and identities.


The main goal of this project is to develop confidence-building vaccine messages that are adapted to distinct groups of vaccine-hesitant individuals. The design and implementation of such messages requires three things. First, a thorough understanding of the nature of the problem to be solved—that is, why are certain populations vaccine-hesitant? Second, how does the target audience conceive of the issue? Finally, the proposed solution—how can we create messaging that successfully encourages vaccine-hesitant individuals to get vaccinated? Audience research into responses to SARS-CoV-2 vaccine is scarce due to the relatively new technologies of the vaccine development (mRNA) and the uncertainty involved with the novelty of the virus itself. Our project leverages the theoretical framework of the integrated behavior model to characterize different audience segments and match messages to their profiles.


Preliminary data were collected from Qualtrics panels on the topic of COVID-19 vaccines (Zhou et al., 2022). A national survey of undergraduate students 18 years and older enrolled in 4-year IHEs in the United States (ages 18-35 years, N = 1,183) was conducted between January 25 and March 4, 2021. At this time, vaccines were only available to those 65 years and older. Participants reported the likelihood of getting the vaccine once it was generally available on a 0-100% scale. Responses of 100% were considered vaccine-confident while responses of less than 100% were considered vaccine-hesitant. Our analysis of the vaccine hesitant subsample revealed five groups.

Group 1, the “Pessimists,” was characterized by low levels of perceived COVID-19 severity and susceptibility with persons reporting a 15% chance of getting vaccinated. This group was extremely concerned about the side effects of the vaccines and did not trust that the vaccines were effective. These beliefs were accompanied by elevated levels of negative emotions and low levels of positive emotions.

Group 2, the “Invincibles,” did not see COVID-19 as a severe risk but also perceived relatively low levels of risks associated with potential side effects of the vaccine. Emotionally, they were ambivalent with a 41% chance of getting vaccinated.

Group 3, the “Rationals,” had relatively mild emotional responses overall but perceived themselves to be most susceptible to COVID-19. While they had relatively high severity perceptions in terms of the side effects of the vaccines, they also reported relatively high inclinations to get the vaccine at 46%.

Group 4, the “Ambivalents,” reported remarkably high levels of perceived COVID-19 severity and susceptibility, as well as increased value in protecting themselves and their cared ones. They also had a relatively strong faith in the effectiveness of the vaccines. Individuals in this group also expressed elevated levels of both positive and negative emotions with an average vaccination chance of 58%.

Finally, the largest group, group 5, the “Borderliners,” reported the highest levels of positive emotions and the lowest levels of negative emotions. This group had the strongest faith in the effectiveness of COVID vaccines and their own ability to receive the vaccines when they are available to them. They were also the least concerned about the possible side effects of the vaccines with a 75% chance of getting vaccinated.

Read the full report here >>