Perceptions, knowledge and attitudes about COVID-19 vaccine hesitancy in older Portuguese adults

Abstract Background Coronavirus 2019 (COVID-19) has become a public-health emergency of international concern. Most efforts to contain the spread and transmission of the virus rely on campaigns and interventions targeted to reduce Vaccine Hesitancy and Refusal (VHR). Objective this study aims to assess the major factors associated with VHR in the older population in Portugal. Methods a nation-wide cross-sectional study was conducted in the older Portuguese population (≥65 years old) through computer-assisted telephone interviewing. Logistic regression was used to determine the adjusted odds ratio (OR) of the independent variables (perceptions, knowledge and attitudes) and of the outcome (VHR). Results the response rate was 60.1% (602/1,001). Perceptions, knowledge and attitudes were strongly associated with VHR probability. A 1-point Likert scale increase in concerns about the vaccines’ efficacy and safety increased the risk of VHR by 1.96 (95% confidence interval [CI]: 1.40–6.28) and 3.13 (95%CI: 2.08–8.22), respectively. A reduction of VHR probability for ‘reliability of the information released by social media’ (OR = 0.34, 95%CI: 0.16–0.70) and for ‘trust in national and international competent authorities’ (OR = 0.34, 95%CI: 0.17–0.69) is also observed per 1-point increase. Conclusions as VHR seems to be strongly associated with perceptions, knowledge and attitudes, the design and promotion of vaccination campaigns/educational interventions specifically targeted at changing these potentially modifiable determinants may help to tackle COVID-19 VHR and achieve a wider vaccine coverage.