Research has shown that political ideology and partisans’ underlying core values correspond to preferences for different goods and services in the United States, including medical advice and vaccinations. Though vaccinations have historically been a bipartisan issue in the US, the politicization of the Covid-19 vaccine suggests health institutions will need to address the cultural barriers to conservative consumption of vaccines to prevent free-riding and future pandemics, write Piergiuseppe Fortunato and Alessio Lombini.

Today’s “Culture Wars” in the United States are hardly new. Gallup’s political ideology trend, collected since 1992, shows that Americans’ ideological positions have not varied significantly over the past three decades. During the Cold War, conservatives and liberals split along attitudes toward socialism and social and racial justice.

Political cleavages reflect different conceptualizations of reality and the core values that guide “correct” behavior. It is a sense of violation of these core values that engenders any type of culture war. While conservatives tend to value purity, loyalty to in-groups, and submission to authority (so called communal values), liberals value care and the ability to empathize: principles that foster fairness and openness toward members of other groups (universal values).

These different sets of values also shape consumer preferences for goods and services in significant ways. For example, liberals consume a wider diversity of activities than conservatives: they attend a greater diversity of live performances, have more hobbies, prefer a greater variety of music genres, and drink more brands of beer. They are also more inclined than conservatives to prefer global experiences (e.g., foreign brands, college courses that come from different cultures, etc.) to local ones.

Political ideologies also correlate with the demand for public health services. Liberals are more likely to trust in science and perceive scientists as credible. Research has also shown that interest in politics and news among liberals has a stronger association with positive attitudes and beliefs toward the scientific community than it does among conservatives. Trust in science and the scientific community in turn shapes individual risk perception and stirs compliance to public health recommendations and instructions.

Nowhere is this mechanic more evident than in the demand for vaccines. In 2009, when a then-new vaccine for the H1N1 virus – commonly known as swine flu – became available, vaccine hesitancy turned out to be highly polarized along partisan lines. Republicans and independents were significantly less likely than Democrats to take the new vaccine or show confidence in the ability of the health authorities to deal with the crisis. A few years later in 2015, Pew Research Center reported that Republicans were more likely than Democrats to advocate against required measle vaccinations for children, despite evidence that unvaccinated individuals were contributing to the spread of a serious outbreak.

The case of Covid-19

The ideological disparity in vaccination rates between Republicans and Democrats has been no different  in the case of Covid-19. In a recent study, we show that actual vaccination rates during the first and second cycles of the US vaccine campaign, which occurred in the first eight months of 2021, have been lower, on average, in counties where residents predominantly voted for the Republican Party in the 2020 presidential election. The phenomenon left some places with a vaccine shortage and others with a glut, especially during the first months of the vaccination campaign in spring 2021.

Figure 1 plots the daily evolution of the proportion of fully vaccinated individuals and individuals who received at least one dose by US counties according to how they voted in the last four presidential elections. Safe democratic counties (depicted in blue) consistently recorded higher shares of the population vaccinated against Covid-19 than Republican strongholds (in red). This gap widened throughout 2021. Interestingly, swing counties (in green) lie right in the middle between the two extreme cases.

Figure 1. Daily proportion of fully vaccinated people and people who received at least one dose by 2008-2020 US party partisanship.

Note: Counties are identified as either Safe Democrat or Safe Republican if the party won all 2008-2020 presidential elections. Alternatively, counties are identified as Swing if Democrats and Republicans alternated as the most voted party at least one time over the 2008-2020 presidential elections.

Political partisanship in the US overlaps with other important social and cultural characteristics that ultimately underpin electoral outcomes. Such an overlap is displayed in Figure 2, which depicts the distribution across US counties of vaccination coverage (panel a), electoral results in 2020 (panel b), relative intensity of communal versus universal values (panel c), and social capital (panel d), which reflects an index of crime levels, number of non-governmental and religious organizations, and electoral turnout.

Darker areas represent counties with higher shares of the population fully vaccinated against Covid-19, higher proportion of votes for the Democratic party, and more diffusion of universal values and of social capital. The figure reveals a close association between these four variables and shows that vaccination coverage is on average much lower in those counties won by Donald Trump in 2020 and where communal values are more common.

Figure 2. Vaccination rate, political ideology, social capital, and moral values in US counties.

territories only. White denotes counties with an insufficient number of observations. Break points are chosen at any ventile.

Policy and vaccine resistance

Building herd immunity through vaccinations has been one of the most successful public health approaches to combating infectious diseases over the last two centuries. In the US, high immunization coverage has drastically reduced or eliminated death from smallpox, measles, polio, diphtheria, pertussis, varicella, and Haemophilus influenzae type b and provided substantial private and public health savings. Routine childhood immunizations in the 2009 birth cohort are estimated to have prevented over 20 million cases and 42,000 deaths in the US with a savings of 14 billion dollars in direct costs.

However, herd immunity against vaccine-preventable diseases is a public good and thus non-excludable and non-rivalrous. Those who forgo vaccination can still benefit from the reduced circulation of the virus. The temptation therefore exists for those who are concerned about the safety of vaccines to “free ride” on the vaccinations of others. This was a particularly heightened problem in the case of Covid-19 as much of the population voiced concerns that the unprecedented expedited approval process for the vaccines might have overlooked possible negative side effects.

The US federal and state governments have historically adopted different strategies to address vaccine resistance. The first, public school immunization mandates, have forced parents to vaccinate their children if they wish to enroll them in public schools. Massachusetts was the first state to enact a school vaccination mandate in 1810 when it gave local health boards the authority to require vaccinations to prevent smallpox transmission. But it was only in 1977, when the federal government set up the Childhood Immunization Initiative, that all 50 states widely adopted mandatory school vaccinations.

Second, while it is not feasible to make herd immunity itself excludable, it is possible to restrict the community and social activities in which unvaccinated people can participate. For several months during the Covid-19 emergency, access to public places such as restaurants, theaters, and gyms in many US cities was conditional on the ability to show proof of vaccination. Although the scale and disruption of the pandemic is in several ways unprecedented, these kinds of vaccine requirements are not. In 1903, Maine’s government decreed that “no person be allowed to enter the employ of, or work in, a lumber camp who cannot show a good vaccination scar.” Traveling restrictions date back to the smallpox outbreak of the 19th century, when vaccine certification became an internationally recommended approach to managing the spread of infectious disease.

Third, during the early stages of the Covid vaccination campaign, many states offered rewards in addition to punishments (in the form of exclusion) to incentivize vaccine uptake. For example, some states tried offering free beverages at restaurants or a ticket for a $5 million lottery to encourage more people to get vaccinated, although these tactics only produced a  minimal effect on daily vaccination rates.

Freedom from sickness?

The suite of tactics available to policymakers to address free-riding the Covid-19 vaccine have been able to go only so far in overcoming concerns and moral positions against the vaccine. The financial carrots and sticks deployed to incentivize vaccination have run aground conservative values in the US that are difficult if not impossible to quantify and plug into a cost-benefit analysis. Many conservatives see vaccination mandates and campaigns as an affront to civil liberties, a position many Republican elected officials have accepted in state legislation prohibiting private businesses from requiring Covid-19 vaccinations.

The political evolution of the Covid-19 vaccine recalls a similar evolution in the marketing and market for gun ownership, once predominantly a product for sportsmanship and hunting that the NRA rebranded as one for self-defense. Similarly, making vaccines a more palatable product for conservatives will in part require a marketing strategy that aligns vaccinations with conservative core values. Private companies in the US have become adept at adjusting market strategies to appeal to liberals or conservatives, but reaching consumers starting from an adverse position will be more difficult. Research on the cultural barriers to certain markets and cultural influence on demand for certain products is still a nascent field of research; the successes and failures of the United States’ vaccine campaigns demonstrate its importance.

Disclaimer: The views expressed in this article belong to the authors alone and do not necessarily reflect those of their affiliated institutions, including the United Nations Conference on Trade and Development.