Community acceptance and willingness-to-pay for a hypothetical Zika vaccine: A cross-sectional study in Indonesia

BACKGROUND

Understanding people's perceptions of the economic benefits of a potential Zika vaccine (ZV) is critical to accelerating its introduction into either public sector programs or private market. The aim of this study was to assess the acceptance and willingness-to-pay (WTP) for a hypothetical ZV and the associated explanatory variables in Indonesia.

METHODS

We conducted a health facility-based cross-sectional study in Aceh and West Sumatra province from 1 February to 13 June 2018. Patients who visited outpatient departments, have had children or were expecting their first child, were approached and interviewed to collect information on acceptance, WTP, demographic and socio-economic variables and attitudes towards childhood vaccines. Associations of explanatory variables influencing acceptance and WTP were assessed using logistic regression and linear regression analysis, respectively.

RESULTS

In total, 956 respondents were included in the final analysis of acceptance, of whom 338 (35.3%) expressed their WTP. We found that 757 (79.1%) of the respondents were likely to be vaccinated and to recommend their partner to be vaccinated. Higher educational attainment, having a job, having heard about Zika and a good attitude towards childhood vaccination were associated with ZV acceptance in the univariate analyses. In the multivariate analysis, attitude towards childhood vaccination was the strongest predictor for ZV vaccination. We found the geometric mean and median of WTP was US$ 13.1 (95% CI: 11.37-15.09) and US$ 7.0 (95% CI: 4.47-10.98), respectively. In the final model, having heard about Zika, having a job, and higher income were associated with a higher WTP.

CONCLUSION

Although the acceptance rate of the ZV is relatively high in Indonesia, less than 40% of respondents are willing to pay, underscoring the need for a low-cost, high-quality vaccine and public sector subsidies for Zika vaccinations in the country.

Willingness to Participate and Associated Factors in a Zika Vaccine Trial in Indonesia: A Cross-Sectional Study

One of the crucial steps during trials for Zika and other vaccines is to recruit participants and to understand how participants' attitudes and sociodemographic characteristics affect willingness to participate (WTP). This study was conducted to assess WTP, its explanatory variables, and the impact of financial compensation on WTP in Indonesia. A health facility-based cross-sectional study was conducted in eleven regencies in the Aceh and West Sumatra provinces of Indonesia. Participants were recruited via a convenience sampling method and were interviewed. The associations between explanatory variables and WTP were assessed using a two-step logistic regression analysis. A total of 1,102 parents were approached, and of these 956 (86.8%) completed the interview and were included in analysis. Of those, 144 (15.1%) were willing to participate in a Zika vaccine trial without a financial compensation. In the multivariate analysis, WTP was tied to an age of more than 50 years old, compared to 20⁻29 years (odds ratio (OR): 5.0; 95% confidence interval (CI): 2.37⁻10.53), to being female (OR: 2.20; 95% CI: 1.11⁻4.37), and to having heard about Zika (OR: 2.41; 95% CI: 1.59⁻3.65). Participants' WTP increased gradually with higher financial compensation. The rate of WTP increased to 62.3% at the highest offer (US$ 350.4), and those who were still unwilling to participate (37.7%) had a poorer attitude towards childhood vaccination. This study highlights that pre-existing knowledge about Zika and attitudes towards childhood vaccination are important in determining community members being willing to participate in a vaccine trial. Financial incentives are still an important factor to enhance participant recruitment during a vaccine trial.