Vaccines against coronavirus disease 2019 (COVID-19) were developed very rapidly over the course of 2020. Their approval followed shortly after, albeit under conditions of emergency use. However, vaccine hesitancy and unwillingness continue to be a headache for public health planners in much of the world. A new preprint analyzes the factors that contribute to this phenomenon in Australia.
Now that vaccines are being rapidly rolled out in many developed countries, covering sizable chunks of the population, there are some hopes that the pandemic may eventually come to an end. The major change that is expected to follow vaccination of a majority of the people in a region is the relaxation of non-pharmaceutical interventions (NPIs) like social distancing and masking, as well as travel bans between high- and low-incidence regions.
A new study, released as a preprint on the medRxiv* server, reports the results of a survey in Australia on vaccine willingness at two points: the first wave in April 2020, and during November of the same year, when cases had dropped significantly.
Vaccines are key
While the UK has vaccinated over 30 million people, which comprises almost half the population, this figure is only 5% in Australia. However, vaccines are key to developing herd immunity, and thus keeping the most vulnerable people healthy, besides heralding the day when a semblance of normalcy can be restored to social and economic interactions.
Vaccine willingness was explored during the development period, over many countries the world over. It was found to be at about 60% in the USA, near 65% in the UK, 75% in New Zealand, and 85% in Australia.
The participants in April included a high fraction of adults who had been educated up to the university level. This was corrected in the November phase, to represent the Australian population by age, sex and education more accurately.
Thus, the median age of the second sample was slightly less, at around 46 years compared to 48 years, respectively. The overall education level was more uniformly distributed, with about a third each having high school education or less, and certificate I-IV. About 30% had gone up to university.
Compared to the first sample, the second had slightly greater health literacy.
What were the findings?
The April arm of the study indicated that much vaccine hesitancy could be traced to the inability to understand health information, and lower education. Vaccine safety was also a prime concern.
To correct this, better messaging which was more sensitive to local language and culture groups would obviously be necessary.
By November, many restrictions had been lifted, and COVID-19 had ceased to be an impending threat for Australians in their own country. About a quarter of participants in November thought that their chances of becoming sick with COVID-19 were lower, vs. less than a fifth in April.
More participants in the second sample believed that the data on vaccine efficacy in general (not just COVID-19 vaccines) was faked, at 34% vs. 29%.
Similar to the April phase, participants in the November sample also thought that the threat to public health posed by COVID-19 was lower. More than a quarter thought that, in fact, that it had been blown up far beyond its actual proportions, compared to one in five in April.
As might have been expected, vaccine willingness towards the COVID-19 vaccine was also lower in the second sample. While over three in every four participants had expressed willingness to take the vaccine when available in the earlier phase, this had dropped to 70% in November.
About 19% were undecided in the second phase, vs. 16% in April; and 12% vs. 7% were unwilling.
The adjusted probability of willingness dropped by 5%, with the odds being 22% lower than any participant would get the vaccine.
Those who were more likely to be willing to take the vaccine included older people aged 56 to 90 years, those with university education, with the ability to read and understand health information so as to use it in decision making.
They were also likely to have confidence in government and institutional measures against the pandemic, and to consider it a public health threat.
Females, as well as those who considered themselves somehow immune to the virus, and those who frankly disbelieved all vaccine-related data, were less likely to be vaccinated.
When these factors are compensated for, the odds for willingness to take the vaccine are comparable in both samples, indicating that overall, Australians have not changed their stance towards COVID-19 vaccination.
The additional factor driving vaccine unwillingness in the second phase of the survey was the way participants perceived COVID-19 as a public health threat.
Reasons for unwillingness
Free-text responses were solicited in the second phase, to help understand why participants were or were not willing to take the vaccine. These showed that the majority of people chose to get the vaccine because of their sense of moral responsibility, and because there was no reason to refuse it, comprising about a tenth each.
However, the largest proportion chose to protect themselves and others by getting the vaccine (almost one in four of the willing group).
As for those who described their unwillingness, a quarter said they were not convinced it was safe, one in five said they did not trust it, while about one in seven disagreed that the vaccine was necessary.
Among the hesitant, almost a third were afraid of vaccine-related health issues, while almost a quarter said they had not decided yet. About one in five said they needed to know more in order to make their decision.
What are the implications?
During this period, the greatest factor underlying vaccine willingness was the need to protect their families and themselves against the virus.
The researchers point out that “perceived risk is influential in people taking preventative measures, and people also need to believe that the behaviour, in this case having the vaccine, will be effective in reducing their risk.”
This has been confirmed by vaccine uptake in the UK, where the perceived risk is high, compared to the USA, and many other European countries, as well as Australia. This means that public health strategies must concentrate on alerting people to the continuing threat of COVID-19 and the attractiveness of the vaccine.
Secondly, the unacceptably high cost of not being vaccinated, to society in general rather than at a personal level, would appeal to the younger section of the population who are both altruistic and unconvinced of their personal risk.
Thirdly, people tend to interpret facts in terms of what they already believe. However, the expression of uncertainty is more likely to be received on its own merits. This should stimulate the expression of uncertainty about some aspects of the vaccine, such as the exact efficacy or duration of immunity, without detracting from its known protective effect against severe COVID-19.
Transparency about governmental decision-making, and about vaccine side effects, will also go a long way in restoring public confidence. This includes being frank about the minuscule proportion of vaccinated individuals who develop serious blood clots soon after vaccination, as well as allowing for an initial period of uncertainty about the implicated vaccine.
Exploiting the strong trust between the people and the government, as well as doctors, by equipping the latter with knowledge to reassure their patient’s concerns, and to correct false complacency, will also help extend vaccine willingness.
medRxiv publishes preliminary scientific reports that are not peer-reviewed and, therefore, should not be regarded as conclusive, guide clinical practice/health-related behavior, or treated as established information.