Influenza vaccination uptake among health care workers and older adults Insights from mixed-methods research in India and the Netherlands and implications for novel delivery technologies

Seasonal influenza poses a significant and recurring public health burden, yet vaccination uptake among high-risk groups, including older adults and health care workers (HCWs), remains below the targets recommended by the World Health Organization in many countries worldwide. This doctoral thesis aims to illuminate how intradermal (ID) patches could potentially enhance influenza vaccination uptake and access by exploring the social and health care context of influenza vaccine uptake among older adults and HCWs in India and the Netherlands. This thesis draws on applied medical anthropology and public health, using a mixed-methods contrasting case study design that combines semi-structured interviews, observations and questionnaire-based surveys.
The empirical chapters show that vaccination behavior is shaped by a complex interplay of factors on various levels. Cross-national patterns among older adults and HCWs included trust in natural immunity, reliance on non-pharmaceutical prevention and a healthy lifestyle, and a gap in awareness about asymptomatic transmission. Structural barriers differed between contexts, where in India vaccine cost, absent formal policies and language barriers between HCWs and patients operated as direct determinants of vaccine behavior while in the Netherlands timing of the vaccine played a role for HCWs. The COVID-19 pandemic increased awareness of respiratory infection prevention but did not automatically translate into interest in influenza vaccination. By connecting these findings to expert perspectives on ID patches, this thesis shows that ID patches show potential for reducing access barriers, particularly among time-constrained HCWs and in resource-constrained settings, but cannot substitute for health communication, education and program development efforts.