Behavioural Dynamics of Vaccine Hesitancy: The Case of sub-Saharan African Communities

Objective: To understand the dynamics and drivers of vaccine hesitancy and analyse stakeholder engagement and intervention design for immunization at the community level in sub-Saharan Africa. Methods: We applied systems thinking and human-centred design to the local immunization systems in two Rwandese communities. Based on primary data collected at health centres in 2018 and 2019 and the vaccine hesitancy 3C’s framework (confidence, complacency, convenience), we created a system dynamics simulation model to analyse vaccine hesitancy. Several feedback loops between immunization service delivery and vaccine hesitancy were identified and included in the model. The impact of vaccine hesitancy on timely measles immunization coverage and on the health of the population at risk was demonstrated. Findings: The two underlying factors of intent to vaccinate (trust and awareness) are dynamic, revealing the importance of sustainable interventions. Our simulation results show that vaccination campaigns play a critical role in decreasing hesitancy and consequently increasing immunity levels in communities. However, their effects are minimal if not continued, therefore, frequent campaigns are necessary to maintain effects. Moreover, exogenous factors such as COVID-19 and weather conditions further complicate the decision to vaccinate by decreasing the safety of travelling to and being in a health centre. Conclusions: A bottom-up approach revealed context-specific challenges and opportunities for immunization interventions. Stakeholder engagement should continuously be revitalized by co-designing interventions through community engagement. Essentially, intervention implementation should be monitored for sustainability assessment, considering behavioural factors (awareness and trust) as well as environmental factors (e.g., rain seasons) and unexpected events (e.g., COVID-19).