Vaccine decision making among people who inject drugs: Improving on the WHO's 3C model of vaccine hesitancy

The objectives of this study were to 1) identify vaccination rates among PWID in Oregon at a time when vaccines were easily accessible, 2) quantitatively identify convergence with demographic correlates of vaccination willingness and uptake to promote generalizability, and 3) explore the factors PWID were considering when deciding whether or not to receive the COVID-19 vaccine. We conducted a mixed-methods study design including 260 quantitative surveys and 41 in-depth qualitative interviews with PWID, conducted July - September 2021 at syringe services programs in Lane County, Oregon. Among the 260 survey respondents, 37.3% indicated that they had received a COVID-19 vaccine by October 1, 2021. In the same period, an estimated 70.1% of the total Lane County population had completed their COVID-19 vaccinations (not including booster rounds). We explored alignment with the WHO’s 3C model of vaccine hesitancy and identified, instead, five common factors as key motivators for vaccine decisions: confidence, convenience, concern, communication, and community implications among PWID. Interviews with PWID describe systemic barriers which prevented them from accessing healthcare resources. We highlight that our proposed 5C model may more accurately depict how PWID navigate vaccine decisions by incorporating the ways that social inequities, infrastructural barriers, and community values influence an individual’s vaccine deliberation.