Most COVID-19 vaccine hesitancy is rooted in concerns that can be addressed and effectively reduced over time, according to a new study following more than 1.1 million people in England between January 2021 and March 2022 during the COVID-19 pandemic, published in The Lancet.
The study, led by researchers from Imperial College London, found that of the participants initially hesitant about getting a COVID-19 vaccine, 65% went on to get vaccinated at least once.
The findings offer a novel perspective on the main types of vaccine hesitancy during the COVID-19 pandemic. Their potential to be reversed may help inform the targeting and messaging for future roll-outs of novel vaccines.
While vaccine hesitancy is not a new phenomenon, with WHO naming vaccine hesitancy as one of the top 10 global health threats in 2019 [1], reduced uptake of various vaccines including childhood vaccinations against measles and pertussis (whooping cough), remains a major public health concern.
COVID-19 vaccination roll-out began in the UK on 8th December 2020, with a phased strategy that prioritised vaccines on the basis of age and clinical need. "We wanted to look at COVID-19 vaccine hesitancy in more depth to identify groups with more persistent forms of hesitancy and their main concerns. Understanding these drivers is critical to address vaccine uptake and better control disease spreads," explained lead author Professor Marc Chadeau-Hyam from Imperial College London, UK.
Researchers analysed longitudinal survey data from 1.1 million adults (aged 18 and older, 57% female) from the Real-time Assessment of Community Transmission (REACT) Study (at the time of the initial COVID-19 vaccine roll-out between January 2021 and March 2022). They compared vaccine attitudes at enrolment with subsequent vaccination uptake from National Health Service (NHS) vaccination records up to May 7, 2024, to identify categories and drivers of vaccine hesitancy.
During the pandemic, participants were asked whether they had been or intended to get vaccinated. Those who refused the vaccine, or were sceptical about vaccination, were asked about their reasons for hesitancy from a checklist of 23 options as well as a free text option [2].
Vaccine effectiveness and health effects key reasons for hesitancy
Overall, 3.3% (37,982 of 1.1 million) of participants reported some degree of COVID-19 vaccine hesitancy and subsequent vaccination data was available through NHS records linkage for 24,229 (64%) of them. Hesitancy rates declined over time from an initial high of 8% of those surveyed in January 2021, to a low of 1.1% at the start of 2022. There was a small uptick in hesitancy to over 2.2% in February and March 2022 during the Omicron wave (see figure 1 in paper).
The researchers identified eight categories of vaccine hesitancy including concerns about effectiveness and side-effects, perception of low risk from COVID-19 and mistrust of vaccine developers, and fear of vaccines and reactions [3]. Among the hesitant who provided a reason for hesitancy, 41% (12,498 of 30,701) reported concerns around long-term health effects, 39% (11,953) that they wanted to wait to see whether the vaccine worked, and 37% (11,287) that they had concerns about side effects.
Reasons for hesitancy varied across demographic groups with, for example, men more likely than women to report not feeling COVID-19 was a personal risk (18% vs 10%); women more likely to be worried about fertility-related consequences (21% vs 8%), while those aged 74 years or older were more likely to be against vaccines in general compared with 18-24 year olds (12% vs 2.5%).
The analysis of subsequent vaccination behaviour found that the likelihood of remaining unvaccinated was higher for older people, women, people of Black ethnicity, people who were unemployed or living in deprived areas, those with a history of COVID-19, and people with a lower level of education.
Majority of vaccine hesitant individuals got vaccinated
People who reported the most common reasons for hesitancy (i.e., those related to vaccine efficacy or health concerns), were most likely to change their mind and subsequently get vaccinated against COVID-19 (see figure 6 in paper).
In contrast, people expressing hesitancy relating to lack of trust, perception of low personal risk, and general anti-vaccine sentiment were two to three-times less likely to get vaccinated compared to those who did not report these reasons.
"We show that certain types of vaccine hesitancy are more readily addressed than others, for example concerns relating to pregnancy or breastfeeding," said co-author Professor Helen Ward from Imperial College London and the National Institute for Health and Care Research Imperial Biomedical Research Centre, UK. "Our study suggests that as the vaccine was rolled out, public confidence increased and the original vaccine scepticism was largely overcome."
According to co-author Professor Paul Elliott from Imperial College London, "What we learned from the COVID-19 experience is the importance of ensuring that people have access to reliable and trusted information so they can make well-informed decisions about their personal health choices. Reliable, easy-to-understand information, for example, on vaccine effectiveness and potential risks, is of particular importance in the case of a public health emergency such as COVID-19, which involved the rapid deployment at-scale of new vaccine technologies."
The authors acknowledge some limitations of the study, including that NHS vaccine records and self-reported vaccine status showed some inconsistencies, likely reflecting both imperfect recall and imperfect coverage in the NHS data. Additionally, vaccine hesitant respondents were less likely to consent to NHS record linkage, potentially introducing selection bias, which may limit the generalisability of the findings.
Writing in a linked Comment, Professor Silvio Tafuri from the University of Bari Aldo Moro, Bari, Italy (who was not involved with the study) underscored the "valuable contribution" of the study and concluded, "whereas these data reflect the extraordinary setting of SARS-CoV-2 vaccination, it is crucial to ascertain whether similar drivers of hesitancy affect ordinary (ie, routine or seasonal) vaccinations, in order to guide context-specific public health interventions at the micro, meso, and macro levels."
PLEASE USE THE FOLLOWING, WHICH WILL GO LIVE AT THE TIME THE EMBARGO LIFTS: http://www.thelancet.com/journals/lancet/article/PIIS0140-6736(25)01912-9/fulltext
