A quarter of UK adults have a potential phobia to injections.
The study participants were asked to rate their anxieties about needles and blood - and about their willingness get a COVID-19 vaccine.
The researchers found that a quarter of the UK adult population have a potential phobia of vaccines; and they were twice as likely to be hesitant about getting a COVID-19 vaccine - meaning they would put off getting vaccinated or never get the jab.
If all injection anxiety in the population is removed then just over 10% of instances of vaccine hesitancy might disappear too, according to the study.
Professor Daniel Freeman, study lead, Department of Psychiatry, University of Oxford, said: 'For people with injection phobia the sight, say, of a hypodermic needle will prompt an initial increase in heart rate and blood pressure. This may be swiftly followed by a sudden decline in both. When that happens, some people faint.
'The COVID-19 vaccination programme means that almost everyone has had - or will soon have - to face the needle. People may certainly think twice about joining a queue for a vaccine if they fear that they might topple to the ground.'
The survey shows that COVID-19 vaccine hesitancy is a little higher among young people and certain ethnic minority groups too because they are sceptical about the jab and fearful about being the injection.
Professor Freeman continues: 'When it comes to controlling COVID-19, every vaccination counts. There is much that can be done to help people overcome their fear of needles. Cognitive behavioural therapy is typically fast and effective -- and can even be successfully given in group sessions. Treatment involves gradual exposure to needles and injections, beginning with simply showing pictures and videos.
'Fainting can be tackled too. Patients can be taught how to recognise the early signs of a dip in their blood pressure and to combat this drop by applied muscle tension.'
Professor Helen McShane, Professor of Vaccinology at the University of Oxford, highlighted that: 'There are many different reasons for why people are hesitant about receiving a vaccine. A fear of needles is a significant factor in up to 10% of people who are vaccine hesitant.
'Whilst needle free routes of vaccination, such as via the nose, are being explored, at present the only approved routes of vaccination for COVID-19 vaccines are by injection. Understanding the underlying causes of this helps us address specific interventions that ultimately will increase vaccine uptake.'
Professor Sir Andrew Pollard, Director of the Oxford Vaccine Group at the University of Oxford said: 'The coronavirus as a public health threat remains with us and those who are unvaccinated will continue to be at risk. Strategies to address protection for the unvaccinated are urgently needed, including getting access to vaccines for those without it and addressing fears and concerns of those who decline.'
The Oxford Coronavirus Explanations, Attitudes, and Narratives Survey (OCEANS III) was conducted between 19 January and 5 February 2021.
The study was funded by the NIHR Oxford BRC and the NIHR Oxford Health BRC.