Public's confidence in vaccines plummets since Covid pandemic

It's one of the greatest achievements of modern science. Within only a year of SARS-CoV-2 (the coronavirus that causes Covid-19) being identified, safe and effective vaccines were developed, tested, and had begun to be rolled out. Since the first doses were administered nearly two years ago, they're estimated to have saved tens of millions of lives. And yet Covid vaccines attracted considerable opposition before their development was even complete.

While vaccine hesitancy is not a new phenomenon, Covid vaccines were met with particularly virulent hostility among conspiracy theorists and other anti-vaxxers. Meanwhile, the vaccines' rapid development and approval gave way to a new group of vaccine sceptics. These people don't consider themselves 'anti-vaxxers', and didn't necessarily oppose other vaccinations, but had concerns over the speed at which Covid vaccines were tested and approved.

This leads to the question of whether, despite the undeniable success of Covid vaccination campaigns, public confidence in vaccines has decreased since the onset of the pandemic. My student and I sought to answer this question in our recently published study, in which we compared vaccine confidence pre-pandemic and since the rollout of Covid vaccines. We compared the results of two online surveys carried out in November 2019 and January 2022, involving more than 1,000 adults.

The survey responses showed that confidence in vaccinations in the post-pandemic group was considerably lower than in the pre-pandemic group. A drop in vaccine confidence was observed regardless of participants' age, gender, religious beliefs, education and ethnicity. One notable difference between the two surveys was that while in the pre-pandemic group middle-aged participants were significantly more vaccine-hesitant than their younger peers, this was not the case for the 2022 group. This observation could be partly explained by the fact that Covid is known to cause more serious illness in older patients, whereas it doesn't commonly lead to hospitalisation and death in young people.

So it's conceivable that older people felt more motivated to get their jab, and were more appreciative of the protection it afforded them. Both in 2019 and 2022, participants who held religious beliefs were significantly more vaccine-hesitant than atheist and agnostic ones. Meanwhile, respondents from black and Asian backgrounds were more hesitant than those of white ethnicity. There was no association between gender and vaccine confidence in either survey. While providing useful insights into how the pandemic affected public perspectives on vaccination, this study does have limitations. When we ran the first survey in 2019, we couldn't have expected a pandemic to break out only a few months later.

So the study was not originally designed to follow up the participants' opinions over time (called a longitudinal study). Instead, we used the same methods to recruit a second group of participants for the 2022 survey, and asked them the same questions so we could compare the outcomes (a cross-sectional study). As a result, our findings should be interpreted with caution, as they don't reflect the changing opinions of the same group of people over time, but rather provide snapshots of two comparable groups at two distinct moments in time.

We did, however, add a single question to the 2022 survey asking participants to report their change in vaccine confidence since Covid. Nearly one in four said their confidence in vaccines had dropped since the pandemic. How can we rebuild declining vaccine confidence? Our study is consistent with other research suggesting that vaccine confidence may be yet another victim of the Covid pandemic. Promoting confidence in vaccines is crucial to help us fight infectious diseases that are already among us, as well as new ones that will undoubtedly emerge in the future.

So how can we address this challenge? A key element is to reassure the public about the safety of vaccines. Although, like all medications, they carry a very small risk of serious side-effects, these risks are minuscule compared with the damage caused by the diseases they protect against. For example, in the case of Covid, many people hesitate to get vaccinated because they're concerned about the rare side-effect of myocarditis (inflammation of the heart muscle). However, abundant clinical evidence indicates that a Covid infection carries a much higher risk of myocarditis than getting vaccinated – more than sevenfold. Confidence in vaccinations can be fostered by ensuring clear communication from governments and public health services and promoting science literacy at all levels. This should happen in schools, but also among adults, particularly those with caring responsibilities, such as parents, carers and healthcare workers.

(The author is an Associate Head (Students), School of Biological Sciences, University of Portsmouth)