Vaccine Hesitancy and Diplomacy in Latin America

This area of my research studies the political drivers of vaccine hesitancy, as well as the political effects of vaccine diplomacy in the context of the COVID-19 pandemic.

The shot, the message, and the messenger: COVID-19 vaccine acceptance in Latin America

with Sarah Z. Daly, John Marshall, Oscar Pocasangre, Julian Gerez, and Pablo Argote Tironi, npj Vaccines no. 118 (2021).

Herd immunity by mass vaccination offers the potential to substantially limit the continuing spread of COVID-19, but high levels of vaccine hesitancy threaten this goal. In a cross-country analysis of vaccine hesitant respondents across Latin America in January 2021, we experimentally tested how five features of mass vaccination campaigns---the vaccine’s producer, efficacy, endorser, distributor, and current population uptake rate---shifted willingness to take a COVID-19 vaccine. We find that citizens preferred Western-produced vaccines, but were highly influenced by information about factual efficacy. Vaccine hesitant individuals responded to vaccine messengers with medical expertise over political, religious, or media elite endorsements. Citizen trust in foreign governments, domestic leaders, and state institutions moderated the effects of the campaign features on vaccine acceptance. These findings can help inform the design of unfolding mass inoculation campaigns.

Messaging interventions that increase COVID-19 vaccine willingness in Latin America

with Sarah Z. Daly, John Marshall, Oscar Pocasangre, Julian Gerez, and Pablo Argote Tironi. PLoS ONE 16 no. 10 (2021).

Governments are now distributing safe and effective COVID-19 vaccines. Once vaccines are widely available, attaining herd immunity will depend on individuals choosing to vaccinate---and doing so quickly enough to outpace mutations. However, our online surveys from January 2021 in six Latin American countries document that only 59% of respondents would get vaccinated and the average individual would wait 4.3 months before vaccinating. Focusing on hesitant respondents, we then experimentally assess messages designed to counteract informational deficiencies and collective action problems that may drive hesitancy. Several actionable findings emerge. First, basic vaccine information persuades around 8% of hesitant individuals to become willing to vaccinate and reduces their intention to wait before vaccinating by 0.4 months. Second, priming the social approval benefits of vaccination similarly increases vaccine willingness, and outperforms priming economic or altruistic benefits of vaccination. Third, individuals are more likely to vaccinate if they believe herd immunity will be achieved.

Vaccine Diplomacy: How Covid-19 Vaccine Distribution Increases Trust in Foreign Governments in Latin America

with Sarah Z. Daly, John Marshall, Oscar Pocasangre, and Julian Gerez. Under review.

The distribution of COVID-19 vaccines has profound implications for global health. Given the scarcity of vaccines in the Global South, vaccine distribution has created opportunities for vaccine developers---including China, India, Russia, the UK, and the US---to improve their reputations in emerging markets. Leveraging panel surveys conducted in January and May of 2021, we evaluate whether ``vaccine diplomacy'' affects trust in foreign governments among vaccine-hesitant respondents in six Latin American countries. We find that personally receiving a vaccine durably increased trust in the government of the country where that vaccine was developed. Furthermore, providing information about the aggregate distribution of vaccines within a respondent's country also increased trust in the governments of the countries where more vaccines were developed. These increases in trust---which are most pronounced for China---appear to reflect perceptions of a common good motivation. Vaccine distribution may then cultivate soft power that could facilitate further economic or political integration.