Serious Underlying Medical Conditions and COVID-19 Vaccine Hesitancy: A Large Cross-Sectional Analysis from Australia

Daphne Day, Lisa Bernadette Grech, Mike Nguyen, Nathan Bain, Alastair Kwok, Sam Harris, Hieu Chau, Bryan Chan, Richard Blennerhassett, Louise M Nott, Nada Hamad, Annette Tognela, David Hoffman, Amelia McCartney, Kate Webber, Jennifer Wong, Craig Underhill, Ben Sillars, Anthony Winkel, Mark SavageBao Loe, Daniel Freeman, Eva Segelov, on behalf of the CANVACCS, DIABVACCS and MSVACCS Investigators

Research output: Contribution to journalArticleResearchpeer-review

10 Citations (Scopus)


As COVID-19 vaccinations became available and were proven effective in preventing serious infection, uptake amongst individuals varied, including in medically vulnerable populations. This cross-sectional multi-site study examined vaccine uptake, hesitancy, and explanatory factors amongst people with serious and/or chronic health conditions, including the impact of underlying disease on attitudes to vaccination. A 42-item survey was distributed to people with cancer, diabetes, or multiple sclerosis across ten Australian health services from 30 June to 5 October 2021. The survey evaluated sociodemographic and disease-related characteristics and incorporated three validated scales measuring vaccine hesitancy and vaccine-related beliefs generally and specific to their disease: the Oxford COVID-19 Vaccine Hesitancy Scale, the Oxford COVID-19 Vaccine Confidence and Complacency Scale and the Disease Influenced Vaccine Acceptance Scale-Six. Among 4683 participants (2548 [54.4%] female, 2108 [45.0%] male, 27 [0.6%] other; mean [SD] age, 60.6 [13.3] years; 3560 [76.0%] cancer, 842 [18.0%] diabetes, and 281 [6.0%] multiple sclerosis), 3813 (81.5%) self-reported having at least one COVID-19 vaccine. Unvaccinated status was associated with younger age, female sex, lower education and income, English as a second language, and residence in regional areas. Unvaccinated participants were more likely to report greater vaccine hesitancy and more negative perceptions toward vaccines. Disease-related vaccine concerns were associated with unvaccinated status and hesitancy, including greater complacency about COVID-19 infection, and concerns relating to vaccine efficacy and impact on their disease and/or treatment. This highlights the need to develop targeted strategies and education about COVID-19 vaccination to support medically vulnerable populations and health professionals.

Original languageEnglish
Article number851
Number of pages13
Issue number6
Publication statusPublished - Jun 2022


  • cancer
  • COVID-19
  • diabetes
  • multiple sclerosis
  • vaccine hesitancy

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