Vaccine nationalism among the public: A cross-country experimental evidence of own-country bias towards COVID-19 vaccination.

What types of vaccines are citizens most likely to accept? We argue that citizens' identification with their nation may lead them to prefer vaccines developed and produced within their national borders, to the exclusion and/or detriment of vaccines from other nations. We administered a conjoint experiment requesting 15,000 adult citizens across 14 individual countries from around the world to assess 450,000 profiles of vaccines that randomly varied on seven attributes. Beyond vaccine fundamentals such as efficacy rate, number of doses, and duration of the protection, we find that citizens systematically favor vaccines developed and produced in their own country of residence. The extent of preference in favor of vaccines developed and produced within the national borders is particularly large among citizens who identify more strongly with their nation, suggesting nationalism plays a role in explaining the bias in favor of vaccines developed and produced locally. This public opinion bias on vaccine preferences has significant theoretical and practical implications.