Introduction of COVID-19 vaccine passports in the UK may lower vaccination inclination

Introducing COVID-19 vaccine passports in the UK could see people who are willing to get vaccinated do so more quickly, but have the converse effect upon those who have concerns, especially when passports cover domestic activities, suggests a new study published in EClinicalMedicine.

Led by the London School of Hygiene & Tropical Medicine (LSHTM) and St Andrews University, the study involved a survey of more than 16,000 UK adults in April 2021. Respondents were asked their intent to receive a vaccination, and if vaccine passports were introduced for domestic or international use, how would this impact their decision.

Overall, the study found that passports may lower vaccination inclination by 3.6% if introduced for domestic use and 1.7% for international use. Younger adults, Black / Black British groups, and non-English speakers stating lower inclination to vaccinate than others if passports were introduced. This was also found to be the case for some work statuses, including part-time employed and looking after the home or family.

The researchers call for further evidence on the impact of restrictions requiring vaccine certification, including studies on the impact of these restrictions on vaccine confidence and willingness among  those individuals and communities who are already more hesitant about vaccination.

Dr Alex de Figueiredo from LSHTM who study first author, said:"Vaccine passports have been cited as a way to aid the reopening of society during and after the pandemic. However, although vaccine incentivization has been cited as a motivating factor for vaccine passports, it is unclear whether vaccine passports are likely to increase inclination to accept a COVID-19 vaccine. This study helps plug that knowledge gap.

"The data suggest that passports receive popular support, however, this is predominately among the vaccinated or among those who state a firm intention to vaccinate. What worries us is the possibility of a 'vaccine passport paradox' – a scenario in which passports in the UK may accelerate the rate at which the population is vaccinated while simultaneously lowering the level of that maximum."  

The team conducted a large-scale national survey in the UK of more than 16,000 adults between 9 and 27 April 2021, using techniques to ensure the sample was nationally representative. Respondents were asked 'If a COVID-19 certificate or passport was required to attend social events in the UK would you be more or less inclined to accept a COVID-19 vaccine'? and 'If a COVID-19 certificate or passport was required for international travel, would you be more or less inclined to accept a COVID-19 vaccine?'

Those surveyed were asked to respond on on a five-point scale, which ranged from 'much less likely' to 'much more likely'.

A large minority of respondents reported that vaccination passports for domestic use (46·5%) or international travel (42·0%) would make them no more or less likely to accept a COVID-19 vaccine. A sizable minority of respondents also state that they would 'definitely' accept a COVID-19 vaccine and that vaccine passports would make them more likely to vaccinate (48·8% for domestic use and 42·9% for international travel).

However, the introduction of vaccine passports would likely lower inclination to accept a COVID-19 vaccine once baseline vaccination intent has been adjusted for. This decrease is larger if passports were required for domestic use rather than for facilitating international travel.

Being male and having degree qualifications is associated with a decreased inclination to vaccinate if passports were required while controlling for baseline vaccination intent for domestic use, while Christians have an increased inclination over atheists or agnostics.

Alex de Figueiredo said: "From nightclubs to international travel, vaccine passports are already playing a big part in many people's lives. However, our study reveals that these policies could indirectly discriminate along socio-demographic lines, shutting out marginalized groups from society."

The research team say an added concern is recent data from the UK and Israel which suggest a much higher rate of breakthrough infections than was expected through clinical trials, so it unlikely vaccines – by themselves – will provide herd immunity.

Alex de Figueiredo said: "Given breakthroughs and high vaccination rates, it is likely that the additional public health burden from the unvaccinated is very small. Encouraging positive public health behaviors regardless of vaccination status such as staying at home if you have symptoms, may yield overall higher public health benefits, without many of the costs. Before implementing vaccine passports, we must assess their overall public health impact."

The researchers say change in inclination is strongly connected to stated vaccination intent and will therefore unlikely shift attitudes among Black or Black British respondents, younger age groups, and non-English speakers.

Lower vaccination inclination in socio-demographic groups that are less confident in COVID-19 vaccines is a concern. As these groups tend to cluster geographically in large urban areas, caution should be exercised around any public health intervention that may undermine positive health-seeking behaviors in areas at high epidemic-risk."

Prof Heidi Larson, Director of the Vaccine Confidence Project

The authors acknowledge limitations of the study, including people may have over-stated their intention to do what the Government, health professions and media are heavily promoting, data collected is not the same as actual vaccination uptake and attitudes to passports may not be static.