Vaccine hesitancy was evident in mid-2021 in people receiving cancer care or surveillance for a current or past solid or haematological cancer diagnosis, Australian research shows.
Responses to an online survey from 1,073 adults with oncology appointments across three Victorian health services found 34.8% were unvaccinated despite being in the Phase 1B priority group for vaccination.
The study, published in the Asia Pacific Journal of Clinical Oncology, found that only 26.4% of the vaccinated group were double-vaxxed.
For the 161 patients with haematological cancers, 105 were vaccinated and 56 were not.
Higher vaccine uptake was significantly associated with older age, male gender, English as a first language, longer time since cancer diagnosis and not being on current anticancer treatment.
Participants with gastrointestinal cancers were significantly less likely to be vaccinated.
Just over half (58%) of the unvaccinated respondents said they would “definitely” or “probably” have a vaccine, while 16% said they would “definitely not” or “probably not.”
Lower intent was observed in younger people, females and people with GI cancers.
Vaccine hesitancy, assessed using the validated Oxford COVID-19 vaccine hesitancy scale, was greater among unvaccinated than vaccinated participants.
“Unlike studies in general populations, we did not find correlations of hesitancy with lower educational level and household income, suggesting disease-related considerations may be stronger determinants of vaccination behaviour in a population affected by cancer,” the study said.
“Cancer stage – whether localised or advanced – did not impact on vaccine uptake or attitude despite the prognostic differences between these groups, reflecting the perception of the immediate threat from COVID-19 compared to the medium/longer term outlook from cancer.”
Fears of side effects and treatment impact
Moderate, significant or life-threatening side effects from the vaccine, including thrombotic complications, were anticipated by 42% of unvaccinated respondents.
“Perceived vaccine-associated side effects were substantial in unvaccinated patients and disproportionately high compared to known side effect profiles described in surveillance reports.”
“The incorrect linkage made by patients between vaccine-related thrombotic events and malignancy-driven prothrombotic tendencies needs to be addressed by treating clinicians,” the investigators said.
Optional comments provided by respondents also revealed uncertainty about the impact of the vaccine on cancer treatment and a lack of reputable information available regarding vaccines for cancer patients and survivors.
“The prominent theme of the desire for clarity of medical advice reflects an information deficit; this gap leads to patients receiving conflicting advice from different clinicians, as described in participant comments.”
“Strategies to address this include coordinated, consistent and evidence-based communication interventions to engage patients with cancer, including material appropriate for culturally and linguistically diverse populations.”
“Oncologists, cancer health professionals, and cancer organisations, including people with lived experience, community service providers, and advocacy groups, should be involved in the design and implementation of these interventions.”
Senior investigator on the study was Professor Eva Segelov from Monash Health and Monash University.