Consumer willingness to pay for a hypothetical chikungunya vaccine in Brazil and the implications

Background: Chikungunya fever is an important infectious disease transmitted by the bite of the mosquitoes. Information about consumers' willingness to pay (WTP) for a hypothetical vaccine can help with future discussions about its possible price. Methods: A cross-sectional study conducted among residents of Minas Gerais, Brazil, regarding their WTP for a hypothetical chikungunya vaccine defined by the authors as having a mean effective protection of 80%. Results: We interviewed 496 individuals. Among these, 23 were excluded from the analysis. Most of the respondents were female (57.3%), had completed at least high school (90.7%), were employed (87.7%) and had private health insurance (62.6%). The median value of the WTP was US$ 31.17 (120.00 BRL) for a unique dose vaccine. The WTP showed a statistical significant correlation with monthly family income and access to private health insurance. Conclusion: This study can contribute to decision-making about potential prices for a chikungunya vaccine once it becomes available in Brazil. We demonstrated the relevance of the anchoring effect as a possible influence applied to the maximum value of the WTP associated with respondents’ preference for a new vaccine. Finally, we encourage the development of a chikungunya virus vaccine to benefit the Brazilian population.