Japanese Encephalitis Vaccine Preferences and Uptake in Western Travelers and Locals: Strategies to Enhance Vaccine Uptake

OBJECTIVES: Understanding the preferences aids in improving Japanese encephalitis (JE) vaccine uptake among populations at risk. This study aimed to determine the preferences, willingness to pay (WTP), and acceptance for JE vaccines of Western travelers and Thai locals. METHODS: A discrete choice experiment was embedded in a survey of 300 Western travelers visiting Thailand and 200 Thai locals from July to November 2023. A mixed logit model assessed the conditional relative importance of vaccine attribute, estimate WTP, and identified preferred vaccines. RESULTS: Western travelers showed a significant preference for European-manufactured vaccines over Thai-produced ones (P < .05). For this group, higher vaccine efficacy was nearly as important as lower cost. In contrast, Thai locals did not favor European manufacturing; for them, affordability was almost twice as important as efficacy. Model-based marginal WTP estimates indicated that Western travelers valued the inactivated Vero cell JE vaccine (JE-VC) higher than live chimeric Vero cell vaccine (JE-CV), (USD 858.16 vs 756.11), whereas Thai locals valued JE-CV higher than inactivated JE-VC, (USD 614.75 vs 483.44). CONCLUSIONS: Vaccine choice differs by population: travelers prioritize efficacy alongside cost, whereas residents emphasize affordability. Travelers also reported higher acceptance in real-world contexts. These divergent preferences underscore the importance of tailoring vaccine policy and further evaluating the immunogenicity of JE-CV after an initial JE-VC dose.